HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kauffman, J. M. Articles by Carey, M. C. Search for Related Content PubMed PubMed Citation Articles by Kauffman, J. M. Articles by Carey, M. C. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 41, 991-1003, June 2000
Copyright © 2000 by Lipid Research, Inc.

Original Article

Fluorocholesterols, in contrast to hydroxycholesterols, exhibit interfacial properties similar to cholesterol

Correspondence to: Martin C. Carey

We used an automated Langmuir-Pockels surface balance to characterize the air;–water interfacial properties of cholesterol (CH) and its derivatives with hydrophilic OH and F substitutions at isologous sites on the sterol body or side chain. We studied 6-fluorocholesterol, 25-fluorocholesterol, 25,26,26,26,27,27,27-heptafluorocholesterol, 7-hydroxycholesterol, 7ß-hydroxycholesterol, 25-hydroxycholesterol and 27-hydroxycholesterol, alone and in mixtures with 1-palmitoyl-2-oleoyl-sn-3-glycero-phosphocholine (POPC). Pressure;–area isotherms of the fluorocholesterols were essentially indistinguishable from CH and all condensed POPC monomolecular layers (monolayers) to variable degrees. Both nucleus-substituted hydroxycholesterols formed expanded monolayers, with lift-offs from baseline 22;–26 Ų/molecule larger than CH, suggesting interfacial tilting; furthermore, in binary mixtures, they condensed POPC monolayers less than CH. In contrast, the side chain hydroxylated CHs were oriented horizontally in the interface at large molecular areas, and became vertical below 140 Ų/molecule with the side chain-OH rather than 3-OH group anchored in the subphase, as evidenced by low collapse pressures and smaller molecular areas than CH. Both side chain hydroxycholesterols expanded POPC monolayers at molar ratios <30%, but induced condensation with higher ratios, suggesting that OH-acyl chain (POPC) repulsion is superceded at higher mole fractions by lateral phase separation and intersteroidal H-bonding.

These studies predict that fluorocholesterols should exhibit intramembrane spatial occupancy nearly identical to CH, whereas nucleus and especially side chain hydroxycholesterols will perturb membrane lipid packing notably.—Kauffman, J. M., P. W. Westerman, and M. C. Carey. Fluorocholesterols, in contrast to hydroxycholesterols, exhibit interfacial properties similar to cholesterol. J. Lipid Res. 2000. 41: 991;–1003.

Supplementary key words: phosphatidylcholine, surface potential, condensation, isotherm, orientation, surface balance, spectroscopic imaging

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				A. Radhakrishnan, Y. Ikeda, H. J. Kwon, M. S. Brown, and J. L. Goldstein From the Cover: Sterol-regulated transport of SREBPs from endoplasmic reticulum to Golgi: Oxysterols block transport by binding to Insig PNAS, April 17, 2007; 104(16): 6511 - 6518. [Abstract] [Full Text] [PDF]

				G. Oradd, P. W. Westerman, and G. Lindblom Lateral Diffusion Coefficients of Separate Lipid Species in a Ternary Raft-Forming Bilayer: A Pfg-NMR Multinuclear Study Biophys. J., July 1, 2005; 89(1): 315 - 320. [Abstract] [Full Text] [PDF]

				J. M. Kauffman, R. Pellicciari, and M. C. Carey Interfacial properties of most monofluorinated bile acids deviate markedly from the natural congeners: studies with the Langmuir-Pockels surface balance J. Lipid Res., March 1, 2005; 46(3): 571 - 581. [Abstract] [Full Text] [PDF]

				Y. Zhang, C. Yu, J. Liu, T. A. Spencer, C. C. Y. Chang, and T.-Y. Chang Cholesterol Is Superior to 7-Ketocholesterol or 7alpha -Hydroxycholesterol as an Allosteric Activator for Acyl-coenzyme A:Cholesterol Acyltransferase 1 J. Biol. Chem., March 21, 2003; 278(13): 11642 - 11647. [Abstract] [Full Text] [PDF]

				S. Meaney, K. Bodin, U. Diczfalusy, and I. Bjorkhem On the rate of translocation in vitro and kinetics in vivo of the major oxysterols in human circulation: critical importance of the position of the oxygen function J. Lipid Res., December 1, 2002; 43(12): 2130 - 2135. [Abstract] [Full Text] [PDF]

				G. Oradd, G. Lindblom, and P. W. Westerman Lateral Diffusion of Cholesterol and Dimyristoylphosphatidylcholine in a Lipid Bilayer Measured by Pulsed Field Gradient NMR Spectroscopy Biophys. J., November 1, 2002; 83(5): 2702 - 2704. [Abstract] [Full Text] [PDF]