Rat ventral prostate microsomal biotransformation of ethanol to acetaldehyde and 1-hydroxyethyl radicals: its potential contribution to prostate tumor promotion.
Rat ventral prostate microsomal fraction was able to biotransform ethanol to acetaldehyde and 1-hydroxyethyl radicals (1HEt) in the presence of NADPH and oxygen. The enzymatic processes involved were not inhibited by desferrioxamine, CO, SKF 525A, 4-methylpyrazole, or polyclonal antibody against P450 reductase but they were significantly inhibited by diethyldithiocarbamate, 2-mercapto-1-methylimidazol, thiobenzamide, or diphenyleneiodonium chloride. Results would suggest the partial participation in these ethanol bioactivation processes of flavin containing monooxygenase (FMO) and/or other flavin dependent oxidases/peroxidases and of a non-iron metal-containing enzymes. Acetaldehyde and free radicals production by prostate microsomal fraction might potentially contribute to tumor promotion in heavy alcohol drinkers.
Castro
G D
GD
Centro de Investigaciones Toxicológicas (CEITOX), CITEFA/CONICET, Buenos Aires, Argentina.
Delgado de Layño
A M A
AM
Costantini
M H
MH
Castro
J A
JA
D000079:Acetaldehyde / Q000378:metabolism / Q000494:pharmacology*; D000428:Alcohol Drinking; D000818:Animals; D000431:Ethanol / Q000494:pharmacology*; D005609:Free Radicals; D008401:Gas Chromatography-Mass Spectrometry; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism*; D009369:Neoplasms / Q000139:chemically induced*; D011467:Prostate / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D019097:Spin Trapping
D005609:Free Radicals; D000431:Ethanol; D000079:Acetaldehyde