title: Steroid-lipid interactions in sonicated dipalmitoyl phosphatidyl choline vesicles: a steady-state and time-resolved fluorescence anisotropy study with all trans-1,6-diphenyl-1,3,5-hexatriene as probe.
abstract: The effect of steroid chemical structure on steroid-lipid interaction is studied in sonicated dipalmitoyl phosphatidylcholine vesicles by steady-state and time-resolved fluorescence anisotropy techniques using diphenylhexatriene as probe. A large number of cholesterol derivatives and steroids, some of them being precursors involved in corticosteroids biosynthesis, has been studied. Addition of a polar group on the side chain in carbon-20 or 22 position evokes considerable difference for the interaction with the bilayer. The carbon-22 position appears to be of critical importance. This observation may be relevant for the functioning of mitochondria from steroid producing tissues, where a stereospecific hydroxylation of cholesterol at the carbon-22R position is required for pregnenolone synthesis.
mesh_terms: D000302:Adrenal Cortex / Q000378:metabolism; D000305:Adrenal Cortex Hormones / Q000096:biosynthesis; D002462:Cell Membrane / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D002784:Cholesterol / Q000502:physiology; D004161:Diphenylhexatriene; D005454:Fluorescence Polarization; D008563:Membrane Lipids / Q000502:physiology; D011663:Pulmonary Surfactants; D013010:Sonication; D013256:Steroids; D013329:Structure-Activity Relationship; D013816:Thermodynamics
chemical_list: D000305:Adrenal Cortex Hormones; D008563:Membrane Lipids; D011663:Pulmonary Surfactants; D013256:Steroids; D004161:Diphenylhexatriene; D002784:Cholesterol