Identification of 7-hydroperoxycholesterol in human liver by liquid chromatography-mass spectrometry.
BACKGROUND
A liquid chromatography-mass spectrometry with an atmospheric chemical ionization interface has been developed to identify simultaneously various oxygenated cholesterols in lipid extracts from alcoholic fatty liver.


METHODS
We collected human liver tissues from alcoholic and control subjects at autopsy. We purified the lipid extracts with solid phase extraction and injected them onto a spherisorb ODS column, by using methanol that contained 10 mM ammonium acetate as a mobile phase and a flow rate of 0.7 ml/min.


RESULTS
We found the presence of 7-hydroperoxycholesterol and other oxysterols (5-cholesten-3beta-ol-7-one, cholest-5-ene-3beta, 7-diol, and 5, 6beta-epoxy-5beta-cholestan-3beta-ol) in alcoholic fatty liver tissues.


CONCLUSIONS
We assume that long-term ethanol ingestion leads to excessive oxidative stress and to the accumulation of cholesterol-derived hydroperoxides and oxysterols in alcoholic fatty liver.