[Regulating and disturbing effects of alpha-tocopherol on lipid bilayers]

Using the high resolution 1H-NMR spectroscopy and spin-probes the influence of alpha-tocopherol on lipid bilayer microviscosity has been studied. It has been established that alpha-tocopherol shows the cholesterol-like action on the physical state of lipid bilayer: alpha-tocopherol increase microviscosity of unsaturated bilayers and decrease microviscosity of saturated bilayers. The character of alpha-tocopherol action is determined by the fatty acidic lipid composition but does not depend on the polar group structure of phospholipid molecule as cholesterol-like action of alpha-tocopherol is found itself in liposomes prepared both from phosphatidylcholine and phosphatidylethanolamine. Analog of alpha-tocopherol without phytol chain 2,2,5,7,8-penthamethyl-6-oxychroman does not show the cholesterol-like action as it is not able to disorder the saturated bilayers.