dihydrochelerythrine and chelerythrine

Chelerythrine (CHE) and dihydrochelerythrine (DHCHE), two typical benzophenanthridine alkaloids, have a wide range of pharmacological activities, such as antibacterial, anti-tumour and antiparasitic activities. To date, the biological activities of CHE and DHCHE are well reported, but the biotransformation of CHE and DHCHE in vivo remains unknown. This study aims to clarify the metabolic pathway of CHE and DHCHE in rat liver microsomes (RLMs) in vitro and in vivo. An ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC/ESI-QTOF-MS) method was developed for metabolites identification of CHE and DHCHE. The urine, feces, bile, and plasma samples and RLMs samples were collected for analyzing the biotransformation pathway of CHE and DHCHE. The result showed that there is a phenomenon of mutual reversible interconversion between CHE and DHCHE in vivo and in vitro. The other biotransformation pathways of CHE and DHCHE including demethylation, hydroxylation, methylene dioxy cycle opening, and glucuronidation mainly occurred in the side chain of benzophenanthridine parent structure. Twenty-five phase I and eight phase II metabolites of CHE, twenty-two phase I and eight phase II metabolites of DHCHE were detected. The results will help to develop a deeper understanding of CHE and DHCHE in vivo process and provide some references for the biotransformation research of other benzophenanthridine alkaloids.

Topics: Animals; Benzophenanthridines; Chromatography, High Pressure Liquid; Chromatography, Liquid; Rats; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

The quaternary benzo[c]phenanthridine alkaloids (QBAs) are an important subgroup of plant secondary metabolites. Their main representatives, sanguinarine (SG) and chelerythrine (CHE), have pleiotropic biological effects and a wide spectrum of medicinal applications. The biotransformation of SG and CHE has only been partially studied while subsequent oxidative transformation of their dihydro derivates, the main metabolites, is practically unknown. The aim of this study was to characterize the biotransformation of CHE and dihydrochelerythrine (DHCHE) in detail, with respect to their more extensive biotransformation than SG. Phase I as well as phase II biotransformation of both compounds was examined in human hepatocyte suspensions. Liquid chromatography with electrospray-quadrupole time-of-flight mass spectrometry (LC-ESI-QqTOF MS) was used for analysis of the metabolites. Using the LC-ESI-QqTOF MS method, we analyzed and then suggested the putative structures of 11 phase I and 5 phase II metabolites of CHE, and 11 phase I and 6 phase II metabolites of DHCHE. For the most abundant metabolites of CHE, DHCHE and O-demethylated DHCHE, their cytotoxicity on primary cultures of human hepatocytes was analyzed. Both metabolites were nontoxic up to 50μM concentration and this indicates decreasing toxic effects for CHE biotransformation products, i.e. DHCHE and O-demethylated DHCHE.

Topics: Benzophenanthridines; Biotransformation; Cells, Cultured; Chromatography, High Pressure Liquid; Hepatocytes; Humans; Spectrometry, Mass, Electrospray Ionization

The herb of Chelidonium majus Linn is known to possess a variety of biological activities and applied in the therapy of various infectious diseases.. To evaluate the in vitro antifungal activity of the active components from Chelidonium majus against clinical drug-resistant yeast isolates.. Active compounds were obtained using bioassay-guided method. Six species of yeast fungi were exposed to the compounds. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined according to the standard broth microdilution method.. Of the six compounds determined, 8-hydroxydihydrosanguinarine (1) and 8-hydroxydihydrochelerythrine (2) demonstrated potent activity with the MIC ranges of 2-80 and 4-100 microg/mL, respectively. Dihydrosanguinarine (3), dihydrochelerythrine (4), sanguinarine (5) and chelerythrine (6) had some degree of antifungal activity.. The overall results provided important information for the potential application of the 8-hydroxylated alkaloids from Chelidonium majus in the therapy of serious infection caused by drug-resistant fungi.

Topics: Alkaloids; Antifungal Agents; Benzophenanthridines; Candida; Chelidonium; Drug Evaluation, Preclinical; Drug Resistance; Heterocyclic Compounds, 4 or More Rings; Humans; Isoquinolines; Microbial Sensitivity Tests; Molecular Structure; Plant Extracts; Plants, Medicinal; Reference Standards

A quaternary benzo[c]phenanthridine alkaloid chelerythrine displays a wide range of biological activities including cytotoxicity to normal and cancer cells. In contrast, less is known about the biological activity of dihydrochelerythrine, a product of chelerythrine reduction. We examined the cytotoxicity of chelerythrine and dihydrochelerythrine in human promyelocytic leukemia HL-60 cells. After 4h of treatment, chelerythrine induced a dose-dependent decrease in the cell viability with IC50 of 2.6 microM as shown by MTT reduction assay. Dihydrochelerythrine appeared to be less cytotoxic since the viability of cells exposed to 20 microM dihydrochelerythrine for 24h was reduced only to 53%. Decrease in the viability induced by both alkaloids was accompanied by apoptotic events including the dissipation of mitochondrial membrane potential, activation of caspase-9 and -3, and appearance of cells with sub-G1 DNA. Moreover, chelerythrine, but not dihydrochelerythrine, elevated the activity of caspase-8. A dose-dependent induction of apoptosis and necrosis by chelerythrine and dihydrochelerythrine was confirmed by annexin V/propidium iodide dual staining flow cytometry. Besides, both alkaloids were found to induce accumulation of HL-60 cells in G1 phase of the cell cycle. We conclude that both chelerythrine and dihydrochelerythrine affect cell cycle distribution, activate mitochondrial apoptotic pathway, and induce apoptosis and necrosis in HL-60 cells.

Topics: Alkaloids; Antineoplastic Agents; Apoptosis; Benzophenanthridines; Caspases; Cell Death; Cell Survival; DNA, Neoplasm; Dose-Response Relationship, Drug; G1 Phase; HL-60 Cells; Humans; Inhibitory Concentration 50; Leukemia, Promyelocytic, Acute; Membrane Potential, Mitochondrial; Time Factors