Biomaterial Database

Biochemical indices of cyclophosphamide-induced lung toxicity. 1984

J M Patel, and E R Block, and C I Hood

Cyclophosphamide (CP) requires metabolic activation for its therapeutic action, and this metabolism results in the formation of two toxic metabolites, acrolein (ACR) and phosphoramide mustard (PM). To determine which metabolite is responsible for CP-induced lung injury, biochemical indices of toxicity and histopathologic changes in the lungs of CP-, ACR-, or PM-treated rats were evaluated. Experimental rats were given 200 mg kg-1 day-1 CP, 5 mg kg-1 day-1 ACR, or 50 mg kg-1 day-1 PM for 1 to 3 days, or were given 100 mg/kg CP for 1 day; control rats received vehicle alone for 1 to 3 days. Twenty-four hr after the last treatment the lungs were analyzed for (a) microsomal NADPH cytochrome c reductase and aniline hydroxylase activities; (b) microsomal lipid peroxide formation; and (c) glutathione content. In rats given 200 mg/kg CP, NADPH cytochrome c reductase and aniline hydroxylase activities decreased 66% (p less than 0.001) and 40% (p less than 0.001), respectively. Lipid peroxidation was increased 100 to 200% (p less than 0.001), and glutathione content was increased 60 to 70% (p less than 0.001). Similar but smaller changes were observed in the lungs of rats given 100 mg/kg CP. In rats given ACR, NADPH cytochrome c reductase and aniline hydroxylase activities decreased 66% (p less than 0.001) and 45% (p less than 0.001), and glutathione content increased 38% (p less than 0.05). In rats given PM, none of the biochemical variables examined were significantly altered. Phenobarbital and SKF 525-A prevented CP-induced biochemical alterations. Despite CP-induced biochemical alterations, no significant light microscopic changes were observed in the lungs. Alterations in lung mixed-function oxidase activity, GSH content, and microsomal lipid peroxide formation are early biochemical indices of CP-induced lung toxicity, and are due at least in part to the reactive metabolite ACR.

UI	MeSH Term	Description	Entries
D008054	Lipid Peroxides	Peroxides produced in the presence of a free radical by the oxidation of unsaturated fatty acids in the cell in the presence of molecular oxygen. The formation of lipid peroxides results in the destruction of the original lipid leading to the loss of integrity of the membranes. They therefore cause a variety of toxic effects in vivo and their formation is considered a pathological process in biological systems. Their formation can be inhibited by antioxidants, such as vitamin E, structural separation or low oxygen tension.	Fatty Acid Hydroperoxide,Lipid Peroxide,Lipoperoxide,Fatty Acid Hydroperoxides,Lipid Hydroperoxide,Lipoperoxides,Acid Hydroperoxide, Fatty,Acid Hydroperoxides, Fatty,Hydroperoxide, Fatty Acid,Hydroperoxide, Lipid,Hydroperoxides, Fatty Acid,Peroxide, Lipid,Peroxides, Lipid
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008297	Male		Males
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D009251	NADPH-Ferrihemoprotein Reductase	A flavoprotein that catalyzes the reduction of heme-thiolate-dependent monooxygenases and is part of the microsomal hydroxylating system. EC 1.6.2.4.	Cytochrome P-450 Reductase,Ferrihemoprotein P-450 Reductase,NADPH Cytochrome P-450 Oxidoreductase,NADPH Cytochrome P-450 Reductase,NADPH Cytochrome c Reductase,Cytochrome P-450 Oxidase,Cytochrome P450 Reductase,Ferrihemoprotein P450 Reductase,NADPH Cytochrome P450 Oxidoreductase,NADPH Cytochrome P450 Reductase,NADPH-Cytochrome P450 Reductase,NADPH-P450 Reductase,Cytochrome P 450 Oxidase,Cytochrome P 450 Reductase,Ferrihemoprotein P 450 Reductase,NADPH Cytochrome P 450 Oxidoreductase,NADPH Cytochrome P 450 Reductase,NADPH Ferrihemoprotein Reductase,NADPH P450 Reductase,Oxidase, Cytochrome P-450,P-450 Oxidase, Cytochrome,P450 Reductase, Cytochrome,P450 Reductase, NADPH-Cytochrome,Reductase, Cytochrome P-450,Reductase, Cytochrome P450,Reductase, Ferrihemoprotein P-450,Reductase, Ferrihemoprotein P450,Reductase, NADPH-Cytochrome P450,Reductase, NADPH-Ferrihemoprotein,Reductase, NADPH-P450
D010634	Phenobarbital	A barbituric acid derivative that acts as a nonselective central nervous system depressant. It potentiates GAMMA-AMINOBUTYRIC ACID action on GABA-A RECEPTORS, and modulates chloride currents through receptor channels. It also inhibits glutamate induced depolarizations.	Phenemal,Phenobarbitone,Phenylbarbital,Gardenal,Hysteps,Luminal,Phenobarbital Sodium,Phenobarbital, Monosodium Salt,Phenylethylbarbituric Acid,Acid, Phenylethylbarbituric,Monosodium Salt Phenobarbital,Sodium, Phenobarbital
D003520	Cyclophosphamide	Precursor of an alkylating nitrogen mustard antineoplastic and immunosuppressive agent that must be activated in the LIVER to form the active aldophosphamide. It has been used in the treatment of LYMPHOMA and LEUKEMIA. Its side effect, ALOPECIA, has been used for defleecing sheep. Cyclophosphamide may also cause sterility, birth defects, mutations, and cancer.	(+,-)-2-(bis(2-Chloroethyl)amino)tetrahydro-2H-1,3,2-oxazaphosphorine 2-Oxide Monohydrate,B-518,Cyclophosphamide Anhydrous,Cyclophosphamide Monohydrate,Cyclophosphamide, (R)-Isomer,Cyclophosphamide, (S)-Isomer,Cyclophosphane,Cytophosphan,Cytophosphane,Cytoxan,Endoxan,NSC-26271,Neosar,Procytox,Sendoxan,B 518,B518,NSC 26271,NSC26271
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005978	Glutathione	A tripeptide with many roles in cells. It conjugates to drugs to make them more soluble for excretion, is a cofactor for some enzymes, is involved in protein disulfide bond rearrangement and reduces peroxides.	Reduced Glutathione,gamma-L-Glu-L-Cys-Gly,gamma-L-Glutamyl-L-Cysteinylglycine,Glutathione, Reduced,gamma L Glu L Cys Gly,gamma L Glutamyl L Cysteinylglycine
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