Inhibition of 2-amino-3-methylimidazo[4,5-f]quinoline-DNA adduct formation in CDF1 mice by heat-altered derivatives of linoleic acid.
Grilled ground beef contains a number of carcinogens, including aminoimidazoazaarenes, such as 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), as well as anticarcinogenic substances, such as heat-generated derivatives of linoleic acid (CLA). In the present study, CLA was administered by gavage every other day to young adult CDF1 mice for a period of 45 days (50 microliters/48 hr for days 1-24 and 100 microliters/48 hr for days 25-45), using trioctanoin as a control. On day 46 all animals received a single oral dose (50 mg/kg) of IQ and tissues were collected 24 hr later. Tissue DNA was purified and analysed for IQ-DNA adducts by 32P-postlabelling assays. Compared with controls, CLA treatment caused a 43.1 and 31.8% inhibition of adduct formation in the livers of male and female mice, respectively. In the lung and large intestine CLA had a 74.2 and 39.4% inhibitory effect, respectively, in the female only, whereas there was no effect in the stomach or small intestine of either sex. In the kidneys of females, CLA treatment inhibited IQ-DNA adduct formation almost completely (95.2%), whereas in the kidneys of males CLA had no effect. It is concluded that CLA inhibits IQ-DNA adduct formation in certain IQ target organs (liver and lung) and non-target organs (large intestine, kidney), but is inactive in other target organs (stomach) and non-target organs (small intestine) of the CDF1 mouse.
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Department of Pathology, Medical College of Ohio, Toledo 43699.
Schut
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HA
D000284:Administration, Oral; D000818:Animals; D016587:Antimutagenic Agents / Q000494:pharmacology*; D001345:Autoradiography; D004247:DNA / Q000096:biosynthesis* / Q000302:isolation & purification; D005260:Female; D006358:Hot Temperature; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000494:pharmacology*; D008297:Male; D051379:Mice; D009153:Mutagens / Q000633:toxicity; D011804:Quinolines / Q000037:antagonists & inhibitors* / Q000633:toxicity
D016587:Antimutagenic Agents; D008041:Linoleic Acids; D009153:Mutagens; D011804:Quinolines; C029216:2-amino-3-methylimidazo(4,5-f)quinoline; D004247:DNA; D019787:Linoleic Acid