Search results for "Ethoxyquin"
showing 9 items of 9 documents
Synthetic antioxidants: biochemical actions and interference with radiation, toxic compounds, chemical mutagens and chemical carcinogens.
1984
Abstract Biological actions of 4 commonly used synthetic antioxidants — butylated hydroxyanisole, butylated hydroxytoluene, ethoxquin and propul gallate — on the molecular, cellular and organ level are compiled. Such actions may be divided into modulation of growth, macromolecule synthesis and differentiation, modulation of immune response, interference with oxygen activation and miscellaneous. Moreover, an overview of beneficial and adverse interactions of these antioxidants with exogenous noxae is given. Beneficial interactions include radioprotection, protection against acute toxicity of chemicals, antimutagenic activity and antitumorigenic action. Possible mechanisms of the antitumorige…
Elevation of hepatic epoxide hydratase activity by ethoxyquin is due to increased synthesis of the enzyme.
1980
Abstract Feeding of the antioxidant ethoxyquin to rats leads to an increase of epoxide hydratase activity in liver microsomes. The apparent half life of the increase is 3–4 days. Elevation of epoxide hydratase activity is also obtained by intraperitoneal treatment of mice with ethoxyquin. This elevation is prevented by concomitant treatment with cycloheximide. When radiolabelled leucine is incorporated into microsomal protein by liver cell fractions from either ethoxyquin-fed or untreated rats, gel electrophoresis reveals that ethoxyquin feeding increases incorporation into epoxide hydratase. These results suggest that the elevation of epoxide hydratase activity by ethoxyquin is due to incr…
Significance of Induction Phenomena
1978
A number of foreign compounds induce the proliferation of the hepatic smooth endoplasmatic reticulum and thereby increase the activity of monooxygenases that metabolize drugs and other foreign compound. With reference to the safety of food additives some antioxidants have been examined by various authors for their inducing capacity, in doses well above those ingested with treated food and above the stipulated accepted daily intake (ADI). Thus feeding of rats with the very high dose of 500 mg/kg body weight of butylated hydroxtoluene (BHT) resulted in an increase in its own oxidative metabolism. Also in monkeys BHT produces an inductive increase of microsomal enzyme activity, cytochrome P 45…
Induction of rat hepatic epoxide hydratase by dietary antioxidants
1979
Abstract Supplementation of rat diet with butylated hydroxytoluene (BHT), butylated hydroxyanisole, or ethoxyquin resulted in increased liver epoxide hydratase activity. The increase was obvious at 0.1% and amounted to 200–400% at 0.5%. Increased activity was accompanied by increased proportion of the epoxide hydratase band in SDS polyacrylamide gels, indicating induction of the enzyme. Ethoxycoumarin deethylase activity and cytochrome b5 concentrations were moderately elevated while cytochrome P-450 concentrations and aryl hydrocarbon hydroxylase activity remained at control levels. Preferential inhibition of monooxygenase activity by metyrapone and not 7,8-benzoflavone, as well as increas…
Ethoxyquin as an inducer and inhibitor of phenobarbital-type cytochrome P-450 in rat liver microsomes.
1977
Abstract The effect of ethoxyquin in vivo and in vitro on drug metabolism in rat liver microsomes was studied. In feeding experiments, a threshold dose of induction was found at 0.05% ethoxyquin for 14 days. At 0.5% ethoxyquin, relative liver weight, cytochrome P-450 content, cytochrome b5 content, ethylmorphine demethylation, and ethoxycoumarin deethylation were increased by a factor of 1.5 to 2. Aryl hydrocarbon hydroxylase activity was, however, not induced but even decreased by 0.5% ethoxyquin in food. Induction of epoxide hydratase was marked, amounting to 400% of control after 0.5% ethoxyquin. The induced enzyme was similar to the phenobarbital-inducible cytochrome P-450 in its CO spe…
Profiling of compounds and degradation products from the postharvest treatment of pears and apples by ultra-high pressure liquid chromatography quadr…
2010
This study deals with a simple strategy to pinpoint potential unknown compounds in full scan mass spectrometry (MS) experiments. Forty samples of apples and pears intended for human consumption were analyzed by ultra-high performance liquid chromatography quadrupole-time-of-flight (UPLC–QqTOF-MS), after extraction of the possible contaminants by rinsing the peel of the fruit with ethyl acetate. The peaks were visually recognized in the total ion chromatogram (TIC). Two major types of postharvest treatments were detected in this set of samples: imazalil (IMZ)/ethoxyquin (EQ) and thiabendazole (TBZ)/diphenylamine (DPA). The present work also describes the metabolites formed by degradation of …
Effect of dietary antioxidants on benzo[a]pyrene metabolism in rat liver microsomes
1983
Feeding of rats with 1% ethoxyquin (EQ) and butylated hydroxytoluene (BHT) but not butylated hydroxyanisole (BHA) increases the formation rate of benzo[a]pyrene (BP)-4,5-dihydrodiol from BP in hepatic microsomes. The production of other BP-dihydrodiols and of BP phenols is decreased after treatment with EQ, BHT and BHA. EQ and BHT are more effective than BHA in inducing epoxide hydrolase (EH) activity towards styrene oxide as the substrate.
Ethoxyquin feeding to rats increases liver microsome-catalyzed formation of benzo(a)pyrene diol epoxide--DNA adduct.
1978
Abstract The ability of rat liver microsomes to catalyze the formation of benzo(a)pyrene 7,8-diol-9,10-epoxide — DNA nucleoside adduct was increased threefold by feeding 0.5% ethoxyquin to the animals. Microsomal epoxide hydratase activity was enhanced i parallel by a factor of 3 while aryl hydrocarbon hydroxylase activity was not induced. Liver microsomes from rat pretreated with 3-methylcholanthrene produced an increased proportion of diol epoxide — DNA adduct when ethoxyquin had been fed to the animals. The main chromatographic peak formed by microsomes from 3-methylcholanthrene treated rats which contains DNA adducts of secondary benzo(a)pyrene phenol metabolites is reduced when the ani…
Effect of Antioxidants on Microsomal Enzymes of Rat Liver
1978
Rat diet was supplemented with butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) or ethoxyquin (EQ) for 14 days, and hepatic microsomal epoxide hydratase (EH) and monooxygenase were subsequently studied in vitro. The antioxidants increased EH activity. The increase was marked with BHT (factor 3) and EQ (factor 4) and was paralleled by an increase in a protein band on SDS polyacrylamide gels which migrated together with purified rat hepatic EH. A slight but nonsignificant increase in cytochrome P450 content and a moderate increase in ethoxycoumarin deethylation and cytochrome b5 content was also observed while aryl hydrocarbon hydroxylase (AHH) activity was not elevated. Irrever…