Biomaterial Database

The effect of cianidanol on rat hepatic monooxygenase activities. 1983

S Beyeler, and B Testa, and D Perrissoud

The antinecrotic hepatoprotective agent cianidanol ((+)-catechin, (+)-cyanidan-3-ol, Catergen) has been tested for its ability to interfere with rat liver monooxygenase activities. In vitro, the drug was found to inhibit biphenyl 4-hydroxylation in microsomes from uninduced rats, and aminopyrine N-demethylase in microsomes from uninduced and PB-treated rats, with IC50 just below 1 x 10(-3) mol/l. The compound is less active in inhibiting biphenyl 2- and 4-hydroxylation and ethoxyresorufin 0-deethylation in microsomes from 3-methylcholanthrene-treated rats. Kinetically, cianidanol behaves as a non-competitive inhibitor in all reactions investigated. It binds to oxidized cytochrome P-450 as a ligand (modified type II binding spectrum). The drug does not decrease levels of cytochrome P-450, but rather protects the enzyme from lipoperoxidation-mediated destruction. In vivo, a single dose of cianidanol does not inhibit [14C]-aminopyrine metabolism. Only after 5 days administration a weak but statistically significant inhibitory effect is detected. The mechanism of action of cianidanol is discussed.

UI	MeSH Term	Description	Entries
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008297	Male		Males
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D010088	Oxidoreductases	The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)	Dehydrogenases,Oxidases,Oxidoreductase,Reductases,Dehydrogenase,Oxidase,Reductase
D001944	Breath Tests	Any tests done on exhaled air.	Breathalyzer Tests,Breath Test,Breathalyzer Test,Test, Breath,Test, Breathalyzer,Tests, Breath,Tests, Breathalyzer
D002392	Catechin	An antioxidant flavonoid, occurring especially in woody plants as both (+)-catechin and (-)-epicatechin (cis) forms.	Catechinic Acid,Catechuic Acid,(+)-Catechin,(+)-Cyanidanol,(+)-Cyanidanol-3,(-)-Epicatechin,(2R,3R)-2-(3,4-Dihydroxyphenyl)-3,5,7-chromanetriol,2H-1-Benzopyran-3,5,7-triol, 2-(3,4-dihydroxyphenyl)-3,4-dihydro-, (2R-cis)-,3,3',4',5,7-Flavanpentol,Catergen,Cianidanol,Cyanidanol-3,Epicatechin,KB-53,Z 7300,Zyma,Cyanidanol 3,KB 53,KB53
D003577	Cytochrome P-450 Enzyme System	A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.	Cytochrome P-450,Cytochrome P-450 Enzyme,Cytochrome P-450-Dependent Monooxygenase,P-450 Enzyme,P450 Enzyme,CYP450 Family,CYP450 Superfamily,Cytochrome P-450 Enzymes,Cytochrome P-450 Families,Cytochrome P-450 Monooxygenase,Cytochrome P-450 Oxygenase,Cytochrome P-450 Superfamily,Cytochrome P450,Cytochrome P450 Superfamily,Cytochrome p450 Families,P-450 Enzymes,P450 Enzymes,Cytochrome P 450,Cytochrome P 450 Dependent Monooxygenase,Cytochrome P 450 Enzyme,Cytochrome P 450 Enzyme System,Cytochrome P 450 Enzymes,Cytochrome P 450 Families,Cytochrome P 450 Monooxygenase,Cytochrome P 450 Oxygenase,Cytochrome P 450 Superfamily,Enzyme, Cytochrome P-450,Enzyme, P-450,Enzyme, P450,Enzymes, Cytochrome P-450,Enzymes, P-450,Enzymes, P450,Monooxygenase, Cytochrome P-450,Monooxygenase, Cytochrome P-450-Dependent,P 450 Enzyme,P 450 Enzymes,P-450 Enzyme, Cytochrome,P-450 Enzymes, Cytochrome,Superfamily, CYP450,Superfamily, Cytochrome P-450,Superfamily, Cytochrome P450
D006899	Mixed Function Oxygenases	Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.	Hydroxylase,Hydroxylases,Mixed Function Oxidase,Mixed Function Oxygenase,Monooxygenase,Monooxygenases,Mixed Function Oxidases,Function Oxidase, Mixed,Function Oxygenase, Mixed,Oxidase, Mixed Function,Oxidases, Mixed Function,Oxygenase, Mixed Function,Oxygenases, Mixed Function
D000632	Aminopyrine	A pyrazolone with analgesic, anti-inflammatory, and antipyretic properties but has risk of AGRANULOCYTOSIS. A breath test with 13C-labeled aminopyrine has been used as a non-invasive measure of CYTOCHROME P-450 metabolic activity in LIVER FUNCTION TESTS.	Amidophenazon,Aminophenazone,Dimethylaminophenazone,Dipyrine,Amidazophen,Amidophen,Amidopyrine,Aminofenazone,Dimethyl-N-aminoantipyrine,Dimethylaminoantipyrine,Eufibron,Dimethyl N aminoantipyrine
D000633	Aminopyrine N-Demethylase		Aminopyrine N Demethylase,Demethylase, Aminopyrine N,N Demethylase, Aminopyrine,N-Demethylase, Aminopyrine