The effect of colupulone (a HOPS beta-acid) on hepatic cytochrome P-450 enzymatic activity in the rat.
Colupulone, a component of hops, was examined for its ability to alter rat hepatic cytochrome P-450 enzymatic activity, expression of hepatic cytochrome P-450 mRNA, and in vitro promutagen activation. Colupulone was fed to male Sprague-Dawley rats for 5 days at 0.36% in the modified AIN 76 diet. Three cytochrome P-450 enzymatic activities were measured, and the corresponding steady-state mRNA levels were examined by Northern blot hybridization. Colupulone increased cytochrome P450IIB and P450IIIA steady-state mRNA levels. In vitro promutagen activation was measured in the Ames assay using liver homogenates from each treatment group. Colupulone treatment did not alter the ex vivo cytochrome P-450-mediated activation of aflatoxin B1 or benzo[a]pyrene to their mutagenic forms. The effect of long-term colupulone administration on in vivo cytochrome P-450 enzymatic activity remains to be determined.
Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824-1224.
E B
EB
Shipp
C S
CS
Mehigh
W G
WG
Helferich
D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001140:Aroclors / Q000633:toxicity; D001564:Benzo(a)pyrene / Q000633:toxicity; D002273:Carcinogens / Q000633:toxicity; D020111:Chlorodiphenyl (54% Chlorine); D003512:Cyclohexanones / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000378:metabolism; D004790:Enzyme Induction / Q000187:drug effects; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects* / Q000201:enzymology*; D009152:Mutagenicity Tests; D011285:Pregnenolone Carbonitrile / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D000900:Anti-Bacterial Agents; D001140:Aroclors; D002273:Carcinogens; D003512:Cyclohexanones; D020111:Chlorodiphenyl (54% Chlorine); D011285:Pregnenolone Carbonitrile; D001564:Benzo(a)pyrene; C075356:colupulone; D003577:Cytochrome P-450 Enzyme System