Effect of ethanol exposure on Xenopus embryo lipid composition

Exposure to ethanol is known to alter cell membranes both chemically and biophysically; these effects may be related to the development of tolerance and physical dependence. In the present study, the effects of various concentrations of ethanol (1-250 mM) on the lipid composition after the first 6 days of Xenopus embryo development were investigated, using an in vitro fertilization technique. Lipid analysis revealed: (1) a decrease of the cholesterol/phospholipid molar ratio mainly derived from a higher content of phospholipids; (2) an increase of phospholipid unsaturated fatty acids, especially C20:4 and C20:5, with ethanol concentration of 150-250 mM; (3) a decrease of lipid-bound sialic acid with ethanol concentrations of > or =5 mM. These results underline that sialoglycoconjugates are a more sensitive target of alcohol in comparison with other lipid components. The cultured embryo method certainly represents a useful model for investigation of the direct effects of ethanol on lipid metabolism, excluding maternal interference which can lead to misinterpretation of data.