7-deoxy-13-dihydroadriamycinone and 7-deoxyadriamycin-aglycone

Structural characterization, identification, and quantification of xenobiotics and their metabolic products commonly require the use of at least two different techniques. This has been the case in the analysis of metabolic products of doxorubicin, a widely used fluorescent anthracycline for the treatment of tumors and leukemia. In this work, we combine high-performance liquid chromatography (HPLC) with a tandem laser-induced fluorescence (LIF) and mass spectrometry (MS) detection scheme for the characterization of doxorubicin and its metabolites produced in the postmitochondrial fraction prepared from Fischer 344 rat liver. LIF detection allowed quantification of the metabolic compounds while MS detection aided in the identification of the metabolites. Using this HPLC-LIF-MS methodology, the disappearance of doxorubicin and the appearance of 7-deoxydoxorubicinone and 7-deoxydoxorubicinolone were monitored over the course of 40 min. This application demonstrates the potential of the tandem LIF-MS detection scheme in quantification and characterization of biotransformations of fluorescent xenobiotics of biomedical and environmental relevance. Furthermore, this detection scheme would be particularly relevant in the analysis of fluorescent analytes in complex samples and in validation of methods for the analysis of such samples that typically rely only on LIF detectors.

Topics: Animals; Antibiotics, Antineoplastic; Chromatography, High Pressure Liquid; Doxorubicin; Fluorescent Dyes; Lasers; Liver; Mass Spectrometry; Naphthacenes; Rats

To investigate the diffusion and accumulation of doxorubicin metabolites in the ascites of patients with ovarian cancer following intravenous injection, as a model for intraperitoneal accumulation of drugs.. The concentrations of doxorubicin and its metabolites [Doxorubicinol (Dox-ol), 7-deoxydoxorubicinolone (7d-Dox-ol-on) and 7-deoxydoxorubicinone (7d-Dox-on)] were measured using high-performance liquid chromatography in the serum and in the ascites of seven patients with recurrent ovarian carcinoma suffering from symptomatic ascites and treated with intravenous doxorubicin.. Doxorubicin metabolites accumulated in the peritoneal cavity. The concentrations of the doxorubicin metabolites were initially higher in the serum compared to the ascitic fluid, but following several hours the doxorubicin metabolites became higher in the ascites, and remained detectable in the ascites for up to 168h, long after disappearance from the serum.. Doxorubicin metabolites accumulate in the ascites and are cleared more slowly from the peritoneal compartment than from the serum. Accumulation in the peritoneal cavity with prolonged half-life should be considered when administering medication in patients with ascites.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antineoplastic; Ascites; Chromatography, High Pressure Liquid; Disease Progression; Doxorubicin; Female; Humans; Middle Aged; Naphthacenes; Ovarian Neoplasms; Paracentesis; Prognosis

Drug-transporting P-glycoproteins are abundantly present in the liver and the intestinal wall. We have now investigated their role in the biliary and intestinal secretion of the anticancer drugs doxorubicin (unlabeled: 5 mg/kg) and vinblastine ((3)H-labeled: 1 mg/kg) i.v. administered to wild-type and mdr1a P-glycoprotein knockout [mdr1a(-/-)] mice. At 90 min after drug administration, levels of unchanged drug and metabolites in plasma, intestinal contents, and bile were determined by high-performance liquid chromatography and radioactivity by liquid scintillation counting. The bile of both wild-type and mdr1a(-/-) mice contained only minor amounts of unchanged vinblastine, whereas the total biliary secretion of unknown (3)H-labeled breakdown products was about 25 to 30% of the dose. The direct secretion of unchanged vinblastine through the gut wall was 6.7 and 3.3% of the dose in wild-type and mdr1a(-/-) mice, respectively. The biliary secretion of unchanged doxorubicin decreased from 13.3% of the dose to only 2.4% in the absence of mdr1a P-glycoprotein. Approximately 10% of the dose was secreted as unchanged doxorubicin into the intestinal contents of both types of mice. Thus, the absence of mdr1a P-glycoprotein affects the fate of vinblastine chiefly by diminishing secretion into the lumen of the small intestine, whereas it affects the fate of doxorubicin chiefly by diminishing secretion of parent drug into bile.

Topics: Animals; Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Bile Ducts; Doxorubicin; Female; Intestinal Mucosa; Male; Mice; Mice, Knockout; Naphthacenes; Vinblastine

A sensitive and selective reversed-phase high-performance liquid chromatographic method for the quantification of doxorubicin and its metabolites doxorubicinol, 7-deoxydoxorubicinone and 7-deoxydoxorubicinolone was developed and validated for a variety of murine specimens. Daunorubicin was used as internal standard. Sample pretreatment involved liquid-liquid extraction of 200 microl sample with 1 ml of chloroform-1-propanol (4:1, v/v). Chromatographic separation was achieved isocratically on a LiChrosorb RP-8 analytical column at ambient temperature. The mobile phase consisted of acidified water (pH 2.05)-acetonitrile-tetrahydrofuran (80:30:1, v/v/v). The column effluent was monitored fluorimetrically at an excitation wavelength of 460 nm and an emission wavelength of 550 nm. The lower limits of quantitation were in the range 1.8-2.4 nM. Spiked murine specimens and samples from treated mice were subjected to stability studies. The results demonstrated the importance of validation in all relevant specimens, since the accuracy and precision were highly matrix-dependent. Accuracies and precisions of measured drug concentrations in liver, spleen, muscle, gastrointestinal tissues, diluted bile, feces and urine were lower than in the other matrices. Doxorubicin was unstable in diluted bile, but not in the other specimens. The method is suitable for studying the pharmacokinetics of doxorubicin and its metabolites in mice.

Topics: Animals; Antibiotics, Antineoplastic; Bile; Chromatography, High Pressure Liquid; Doxorubicin; Feces; Female; Humans; Male; Mice; Naphthacenes; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution