Human liver samples from 33 patients were collected at autopsy (controls, n
= 9; fatty liver, n = 12; liver cirrhosis, n = 12), and samples homogenize
d. Lipids extracted with chloroform and methanol were injected into the oct
yl column of a high-performance liquid chromatograph with post-column chemi
luminescence. Liquid chromatography-mass spectrometry was developed to iden
tify 7-hydroperoxycholest-5-en-3 beta-ol (7-OOH). We found that two cholest
erol-derived hydroperoxides, 7 alpha-hydroperoxycholest-5-en-3 beta-ol (7 a
lpha-OOH) and 7 beta-hydroperoxycholest-5-en-3 beta-ol (7 beta-OOH), are pr
esent in significantly elevated amounts (12.4 and 25.0 nmol/g tissue, respe
ctively) in lipid extracts from alcoholic fatty liver, but not in extracts
from alcoholic cirrhotic liver. 7 alpha-OOH and 7 beta-OOH are early interm
ediates produced during free radical-mediated cholesterol oxidation and can
serve as molecular indicators of chain peroxidative damage in cell membran
es. This is the first demonstration of 7 alpha-OOH and 7 beta-OOH accumulat
ions in human liver, and it is presumed to reflect greater oxidative stress
pathology in alcoholic fatty liver.