Inhibition of sulfotransferase in primary cultures of human hepatocytes affecting metabolism and binding of 2-acetylaminofluorene.
The metabolism and DNA binding of acetylaminofluorene (AAF) was investigated in human hepatocytes that were isolated from donor liver tissue by collagenase perfusion. Hepatocytes were treated with 0.01 microM pentachlorophenol (PCP), as a sulfotransferase inhibitor, to investigate the role of sulfotransferase in human bioactivation of aromatic amines. Concentrations of PCP greater than 0.1 microM resulted in cytotoxicity as noted by detachment of cells and atypical morphology. The metabolites of AAF were identified by HPLC as aminofluorene, 7-OH-AAF, 9-OH-AAF, 5-OH-AAF, N-OH-AAF, 1-OH-AAF and 3-OH-AAF. No consistent alteration in the metabolites produced occurred with PCP treatment compared to controls. PCP treatment increased total DNA binding of AAF metabolites compared with controls, suggesting that sulfotransferase does not activate AAF in human hepatocytes. Inhibition of sulfotransferase in human hepatocytes does not decrease DNA binding of AAF metabolites as noted previously with rat hepatocytes. Therefore, PCP may inhibit a detoxication pathway. This study supports N,O-acyltransferase as the critical enzyme for the formation of the major reactive metabolite in human liver.
Monteith
D K
DK
Department of Biological Sciences, Indiana University-Purdue University, Fort Wayne.
D015073:2-Acetylaminofluorene / Q000378:metabolism* / Q000494:pharmacology; D000328:Adult; D001711:Biotransformation; D004247:DNA / Q000378:metabolism; D005260:Female; D006801:Humans; D006881:Hydroxyacetylaminofluorene / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D010416:Pentachlorophenol / Q000494:pharmacology*; D015238:Sulfotransferases / Q000037:antagonists & inhibitors* / Q000378:metabolism
D006881:Hydroxyacetylaminofluorene; D004247:DNA; D015073:2-Acetylaminofluorene; D010416:Pentachlorophenol; D015238:Sulfotransferases