Lipid binding to sterol carrier protein-2 is inhibited by ethanol. Academic Article uri icon


  • Sterol carrier protein-2 (SCP-2) is an intracellular lipid carrier protein that binds cholesterol, phospholipids, fatty acids and other ligands. It has been reported that expression of SCP-2 was increased in brain nerve endings or synaptosomes of chronic ethanol-treated mice and it was shown that cholesterol homeostasis was altered in brain membranes of chronic ethanol-treated animals. Ethanol may interfere with the capacity of SCP-2 to bind cholesterol as well as other lipids. This hypothesis was tested using recombinant SCP-2 and fluorescent-labeled cholesterol, phosphatidylcholine (PC), and stearic acid. The association constants (Ka) of the ligand-SCP-2 complex were in the following order: NBD-cholesterol>NBD-PC>NBD-stearic acid. Ethanol, beginning at a concentration of 25 mM, significantly reduced the affinity of NBD-cholesterol and NBD-PC for SCP-2. Effects of ethanol on the Ka of NBD-stearic acid was significant only at the highest concentration that was examined (200 mM). Ethanol significantly increased the Bmax of NBD-cholesterol for SCP-2 but did not have a significant effect on the Bmax of NBD-PC. Similar results were found for effects of ethanol on the Kas and Bmaxs using pyrene-labeled cholesterol and PC. In conclusion, ethanol beginning at a physiological concentration of 25 mM inhibited binding of cholesterol and PC to SCP-2. However, effects of ethanol on lipid binding to SCP-2 were dependent on the type of lipid. Ethanol in vivo may interfere with lipid binding to SCP-2 and disrupt lipid trafficking within cells.

published proceedings

  • Biochim Biophys Acta

altmetric score

  • 6

author list (cited authors)

  • Avdulov, N. A., Chochina, S. V., Igbavboa, U., Warden, C. S., Schroeder, F., & Wood, W. G.

citation count

  • 62

complete list of authors

  • Avdulov, NA||Chochina, SV||Igbavboa, U||Warden, CS||Schroeder, F||Wood, WG

publication date

  • January 1999