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.

• MeSH
• benzofenantridiny farmakokinetika   MeSH
• biotransformace MeSH
• hepatocyty metabolismus   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací metody   MeSH
• kultivované buňky MeSH
• lidé MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The metabolism of the benzo[c]phenanthridine alkaloids was studied using human hepatocytes which are an excellent model system for biotransformation studies. For analysis of the alkaloids and their metabolites, an electrospray quadrupole ion-trap mass spectrometry (ESI ion-trap MS) connected to a reversed phase chromatographic system based on cyanopropyl modified silica was used. The optimized experimental protocol allowed simultaneous analysis of the alkaloids and their metabolites and enabled study of their uptake into and interconversion in human hepatocytes. The results show that formation of the dihydro metabolite which may be followed by specific O-demethylenation/O-demethylation processes, is probably the main route of biotransformation (detoxification) of the benzo[c]phenanthridines in human hepatocytes. The structure of the main O-demethyl metabolite (2-methoxy-12-methyl-12,13-dihydro-[1,3]dioxolo[4',5':4,5]benzo[1,2-c]phenanthridin-1-ol; 336.1 m/z,) was proposed by the multi-stage MS and quadrupole time-of-flight MS methods using chemically synthesized standard.

• MeSH
• benzofenantridiny analýza   metabolismus   farmakokinetika   MeSH
• biotransformace MeSH
• dospělí MeSH
• hepatocyty chemie   metabolismus   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací metody   MeSH
• isochinoliny analýza   metabolismus   farmakokinetika   MeSH
• kultivované buňky MeSH
• lidé středního věku MeSH
• lidé MeSH
• oxidace-redukce MeSH
• reprodukovatelnost výsledků MeSH
• senioři MeSH
• tandemová hmotnostní spektrometrie metody   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The quaternary benzo[c]phenanthridine alkaloid sanguinarine (SG) is the main component of Sangrovit, a natural livestock feed additive. Dihydrosanguinarine (DHSG) has recently been identified as a SG metabolite in rat. The conversion of SG to DHSG is a likely elimination pathway of SG in mammals. This study was conducted to evaluate the toxicity of DHSG in male Wistar rats at concentrations of 100 and 500 ppm DHSG in feed for 90 days (average doses of 14 and 58 mg DHSG/kg body weight/day). No significant alterations in body or organ weights, macroscopic details of organs, histopathology of liver, ileum, kidneys, tongue, heart or gingiva, clinical chemistry or hematology markers in blood in the DHSG-treated animals were found compared to controls. No lymphocyte DNA damage by Comet assay, formation of DNA adducts in liver by 32P-postlabeling, modulation of cytochrome P450 1A1/2 or changes in oxidative stress parameters were found. Thus, repeated dosing of DHSG for 90 days at up to 500 ppm in the diet (i.e. approximately 58 mg/kg/day) showed no evidence of toxicity in contrast to results published in the literature. In parallel, DHSG pharmacokinetics was studied in rat after oral doses 9.1 or 91 mg/kg body weight. The results showed that DHSG undergoes enterohepatic cycling with maximum concentration in plasma at the first or second hour following application. DHSG is cleared from the body relatively quickly (its plasma levels drop to zero after 12 or 18 h, respectively).

• MeSH
• adukty DNA MeSH
• benzofenantridiny farmakokinetika   krev   toxicita   MeSH
• biochemická analýza krve MeSH
• časové faktory MeSH
• financování organizované MeSH
• ileum patologie   účinky léků   MeSH
• isochinoliny farmakokinetika   krev   toxicita   MeSH
• játra patologie   účinky léků   MeSH
• kometový test MeSH
• krmivo pro zvířata MeSH
• krysa rodu rattus MeSH
• náhodné rozdělení MeSH
• orgánová specificita MeSH
• oxidační stres účinky léků   MeSH
• pilotní projekty MeSH
• plocha pod křivkou MeSH
• poškození DNA účinky léků   MeSH
• potkani Wistar MeSH
• systém (enzymů) cytochromů P-450 účinky léků   MeSH
• testy genotoxicity MeSH
• tkáňová distribuce MeSH
• velikost orgánu účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH

Sanguinarine is an alkaloid with known antibiotic and anti-inflammatory activity and its pharmacokinetics have been studied in the rat after a single oral dose (10 mg kg(-1) body weight). Alkaloid determination in the plasma and liver was carried out by high-performance liquid chromatography-electrospray ionization mass spectrometry (HPLC/ESI-MS). The pharmacokinetic parameters (t(max), c(max), AUC(0-->t) and AUC(0-->infinity)) were determined for sanguinarine and dihydrosanguinarine, the major components detected in plasma. The first step in sanguinarine metabolism in the rat was the reduction of the iminium bond resulting in formation of the less toxic dihydrosanguinarine. Both compounds were completely eliminated from the plasma and liver after 24 h and not detected in urine. After a single oral dose of (3)H-sanguinarine, more than 42% of the ingested radioactivity was present in gastrointestinal tract. Benz[c]acridine, up to date the only sanguinarine metabolite referred to in the literature, was not detected in the plasma, liver or urine.

• MeSH
• akridiny chemie   MeSH
• alkaloidy aplikace a dávkování   farmakokinetika   chemie   krev   MeSH
• antiinfekční látky aplikace a dávkování   farmakokinetika   chemie   krev   MeSH
• aplikace orální MeSH
• benzofenantridiny aplikace a dávkování   farmakokinetika   chemie   krev   MeSH
• časové faktory MeSH
• financování organizované MeSH
• hmotnostní spektrometrie MeSH
• isochinoliny aplikace a dávkování   farmakokinetika   chemie   krev   MeSH
• krysa rodu rattus MeSH
• potkani Wistar MeSH
• tkáňová distribuce MeSH
• tritium MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH