In this work, 35 new derivatives of betulonic, dihydrobetulonic and ursonic acid were prepared including 30 aminothiazoles and all of them were tested for their in vitro cytotoxic activity in eight cancer cell lines and two non-cancer fibroblasts. Compounds with the IC50 below 5 μM in CCRF-CEM cells and low toxicity in non-cancer fibroblasts (4m, 5c, 5m, 6c, 6m, 7b, and 7c) were further subjected to tests of pharmacological parameters yielding the final set for advanced biological evaluation (4m, 5m, 6m, and 7b). It was proved by several methods, that all of them trigger apoptosis via the intrinsic pathway and derivatives 5m and 7b are the most effective (IC50 2.4 μM and 3.6 μM). They are the best candidates to become potentially new anticancer drugs and will be subjected to in vivo tests in mice. In addition, compounds 6b and 6c deserve more attention because their activity is not limited only to chemosensitive CCRF-CEM cell line. Specifically, compound 6b is highly active against K562 leukemic cell line (0.7 μM) and its IC50 activity in colon cancer HCT116 cell line is 1.0 μM. Compound 6c is active in both normal K562 and resistant K562-TAX cell lines (IC50 3.4 μM and 5.4 μM) and both colon cancer cell lines (HCT116 and HCT116p53-/-, IC50 3.5 μM and 3.4 μM).
- MeSH
- antitumorózní látky chemická syntéza chemie farmakologie MeSH
- apoptóza účinky léků MeSH
- fibroblasty účinky léků MeSH
- kultivované buňky MeSH
- kyselina olenalová analogy a deriváty chemie farmakologie MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- membránový potenciál mitochondrií účinky léků MeSH
- mikrozomy chemie metabolismus MeSH
- molekulární struktura MeSH
- proliferace buněk účinky léků MeSH
- terpeny chemická syntéza chemie farmakologie MeSH
- thiazoly chemická syntéza chemie farmakologie MeSH
- triterpeny chemie farmakologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Herein, we report the discovery and structure-activity relationships of 5-substituted-2-[(3,5-dinitrobenzyl)sulfanyl]-1,3,4-oxadiazoles and 1,3,4-thiadiazoles as a new class of antituberculosis agents. The majority of these compounds exhibited outstanding in vitro activity against Mycobacterium tuberculosis CNCTC My 331/88 and six multidrug-resistant clinically isolated strains of M. tuberculosis, with minimum inhibitory concentration values as low as 0.03 μM (0.011-0.026 μg/mL). The investigated compounds had a highly selective antimycobacterial effect because they showed no activity against the other bacteria or fungi tested in this study. Furthermore, the investigated compounds exhibited low in vitro toxicities in four proliferating mammalian cell lines and in isolated primary human hepatocytes. Several in vitro genotoxicity assays indicated that the selected compounds have no mutagenic activity. The oxadiazole and thiadiazole derivatives with the most favorable activity/toxicity profiles also showed potency comparable to that of rifampicin against the nonreplicating streptomycin-starved M. tuberculosis 18b-Lux strain, and therefore, these derivatives, are of particular interest.
- MeSH
- antituberkulotika chemická syntéza farmakologie toxicita MeSH
- Bacteria účinky léků MeSH
- buněčné linie MeSH
- houby účinky léků MeSH
- latentní tuberkulóza farmakoterapie mikrobiologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- mikrozomy metabolismus MeSH
- mnohočetná bakteriální léková rezistence MeSH
- mutageny toxicita MeSH
- Mycobacterium tuberculosis účinky léků MeSH
- oxazoly chemická syntéza farmakologie MeSH
- primární buněčná kultura MeSH
- racionální návrh léčiv MeSH
- rifampin farmakologie MeSH
- thiadiazoly chemická syntéza farmakologie MeSH
- viabilita buněk účinky léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Ivermectin (IVE), one of the most important anthelmintics, is often used in the treatment of haemonchosis in ruminants. The objective of our work was (1) to find and identify phase I and II metabolites of IVE formed by the Barber's pole worm (Haemonchus contortus), and (2) to compare IVE metabolites in helminths with IVE biotransformation in sheep (Ovis aries) as host species. Ultrahigh-performance liquid chromatography/tandem mass spectrometry (UHPLC/MS/MS) was used for this purpose. During in vitro incubations, microsomes (from adult worms or from ovine liver) and a primary culture of ovine hepatocytes were incubated with IVE. In the ex vivo study, living H. contortus adults were incubated in the presence of 1 μM IVE for 24 h. The results showed that the H. contortus enzymatic system is not able to metabolize IVE. On the other hand, 7 different phase I as well as 9 phase II IVE metabolites were detected in ovine samples using UHPLC/MS/MS analyses. Most of these metabolites have not been described before. Haemonchus contortus is not able to deactivate IVE through biotransformation; therefore, biotransformation does not contribute to the development of IVE-resistance in the Barber's pole worm.
- MeSH
- anthelmintika chemie metabolismus terapeutické užití MeSH
- chromatografie kapalinová MeSH
- Haemonchus účinky léků růst a vývoj metabolismus MeSH
- hemonchóza farmakoterapie parazitologie veterinární MeSH
- hepatocyty metabolismus MeSH
- hmotnostní spektrometrie MeSH
- ivermektin chemie metabolismus terapeutické užití MeSH
- kultivované buňky MeSH
- mikrozomy metabolismus MeSH
- nemoci ovcí farmakoterapie parazitologie MeSH
- ovce domácí metabolismus MeSH
- ovce metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Microsomal fraction of fungal cells grabs the attention of many researchers for it contains enzymes that play a role in biotechnologically relevant processes. Microsomal enzymes, namely, CYP450s, were shown to metabolize a wide range of xenobiotic compounds, including PAHs, PCBs, dioxins, and endocrine disruptors, and take part in other fungal biotransformation reactions. However, little is known about the nature and regulation of these membrane-associated reactions. Advanced proteomic and post-genomic techniques make it possible to identify larger numbers of microsomal proteins and thus add to a deeper study of fungal intracellular processes. In this work, proteins that were identified through a shotgun proteomic approach in fungal microsomes under various culture conditions are reviewed. However, further research is still needed to fully understand the role of microsomes in fungal biodegradation and biotransformation reactions.
Aim of this work was to investigate the ability of Lentinus (Panus) tigrinus to degrade and detoxify a chlorobenzoate (CBA) mixture composed of mono-, di- and tri-chlorinated isomers. The degradation process was investigated as a function of both the growing medium (i.e. low N Kirk's and malt extract-glucose medium) and cultivation conditions (i.e. stationary and shaken cultures). The majority of CBAs were quantitatively degraded within the early 15 d from spiking with the notable exception of the double ortho-chlorinated compounds, 2,6-di-, 2,3,6-tri- and 2,4,6-tri-CBA. Analysis of the degradation intermediates indicated the occurrence of side chain reduction, hydroxylation and methylation reactions. Although CBAs stimulated laccase production, in vitro experiments with a purified L. tigrinus laccase isoenzyme demonstrated its inability to participate in the initial attack on CBAs even in the presence of redox mediators; similar results were found with a Mn-peroxidase isoenzyme. Conversely, prompt degradation was observed upon 1h incubation of CBAs with a purified microsomal fraction containing cytochrome P-450 monooxygenase. The nature of some reaction products (i.e. hydroxylated derivatives), the dependency of the reaction on NADPH and its susceptibility to either CO or piperonyl butoxide inhibition confirmed the involvement of L. tigrinus cytochrome P-450 in the early steps of CBA degradation.
- MeSH
- Aliivibrio fischeri metabolismus MeSH
- biodegradace MeSH
- biomasa MeSH
- chemické látky znečišťující vodu analýza metabolismus MeSH
- chlor chemie MeSH
- chlorbenzoáty analýza metabolismus MeSH
- čištění vody metody MeSH
- kultivační média metabolismus MeSH
- kyslík chemie MeSH
- lakasa metabolismus MeSH
- Lentinula metabolismus MeSH
- luminiscence MeSH
- mikrozomy metabolismus MeSH
- peroxidasy MeSH
- substrátová specifita MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- testy toxicity MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVE: Ellipticine is a potent antineoplastic agent exhibiting multiple mechanisms of action. This anticancer agent should be considered a pro-drug, whose pharmacological efficiency and/or genotoxic side effects are dependent on its cytochrome P450 (CYP)- and/or peroxidase-mediated activation to species forming covalent DNA adducts. The target of this study was to investigate a role of CYP and peroxidase enzymes in ellipticine oxidative activation in rats, a suitable model mimicking the fate of ellipticine in humans, in details. The contribution of pulmonary and renal CYP- and peroxidase enzymes to ellipticine metabolic activation is investigated and compared with that found in the liver. METHODS: Ellipticine oxidation and DNA adduct formation in vitro were investigated using microsomes isolated from liver, lung and kidney of rats, either control (untreated) or treated i.p. with a single dose of 40 mg of ellipticine per kg of body weight. HPLC with UV detection was employed for the separation and characterization of ellipticine metabolites. Inhibitors of CYPs and cyclooxygenase (prostaglandin H synthase, COX) were used to characterize the enzymes participating in ellipticine oxidative activation in rat liver, lung and kidney. Ellipticine-derived DNA adducts were detected by 32P-postlabeling. RESULTS: Using α-naphthoflavone, furafylline and ketoconazole, inhibitors of CYP1A, 1A2 and 3A, respectively, we found that the CYP1A and 3A enzymes play a major role in ellipticine activation to species forming DNA adducts in liver microsomes. Because of lower expression of these enzymes in lungs and kidneys, even after their induction by ellipticine, they play a minor role in ellipticine activation in these extrahepatic tissues. Arachidonic acid, a cofactor of COX, increased ellipticine activation in the microsomes of extrahepatic tissues. In addition, indomethacin, an inhibitor of COX, efficiently inhibited formation of ellipticine-derived DNA adduct in these microsomes. Based on these results, we attribute the higher activation of ellipticine in lung and kidney microsomes to COX than to CYP enzymes. CONCLUSION: The results demonstrate that whereas CYP enzymes of 1A and 3A subfamilies are the major enzymes activating ellipticine in rat livers, peroxidase COX plays a significant role in this process in lungs and kidneys.
- MeSH
- adukty DNA účinky léků MeSH
- antitumorózní látky metabolismus MeSH
- biotransformace účinky léků MeSH
- elipticiny metabolismus MeSH
- játra metabolismus MeSH
- krysa rodu rattus MeSH
- ledviny metabolismus MeSH
- mikrozomy účinky léků metabolismus MeSH
- modely u zvířat MeSH
- oxidace-redukce účinky léků MeSH
- peroxidasy fyziologie MeSH
- plíce metabolismus MeSH
- potkani Wistar MeSH
- systém (enzymů) cytochromů P-450 fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: The aim of this study was to assess the effect of various flavonoids on the NADPH:cytochrome P450 oxidoreductase (CYPOR) activity in respect of the reduction of different electron acceptors as well as to study an impact of flavonoids on monooxygenation of a model substrate of cytochrome P450 (CYP). DESIGN: The modulation of CYPOR activity was determined spectrophotometrically based on the time course of the reduction of different electron acceptors. The CYP reduction was monitored via its complex formation with CO, having pronounced the absorption maximum at 450 nm. Finally, effect of CYPOR stimulation by 7,8benzoflavone (ANF) on 7pentoxyresorufin Odepentylation was assayed in the microsomal monooxygenation system using the fluorimetric detection of formed resorufin. RESULTS: The stimulation of CYPOR activity via ANF was found to be associated with following electron acceptors: cytochrome c, potassium ferricyanide, cytochrome b5, but not with CYP. Surprisingly, 5,6benzoflavone, a position isomer of ANF, was ineffective in the CYPOR stimulation as well as the other flavonoids tested. In microsomal preparations, ANF did not markedly enhance the reaction rate of monooxygenation of CYP2B4 model substrate. CONCLUSION: Our results document that among all of the tested flavonoids only ANF is able to stimulate CYPOR activity, however, the ANF-mediated stimulation of CYPOR has no impact on the oxidative metabolism catalyzed by CYP system.
- MeSH
- antioxidancia farmakologie MeSH
- benzoflavony chemie metabolismus MeSH
- beta-naftoflavon chemie metabolismus MeSH
- časové faktory MeSH
- cytochromy b5 metabolismus MeSH
- cytochromy c metabolismus MeSH
- ferrikyanidy metabolismus MeSH
- flavonoidy chemie farmakologie MeSH
- fluorometrie MeSH
- králíci MeSH
- kyselina lipoová farmakologie MeSH
- mikrozomy účinky léků enzymologie metabolismus MeSH
- NADPH-cytochrom c-reduktasa metabolismus MeSH
- oxaziny metabolismus MeSH
- oxid uhelnatý metabolismus MeSH
- oxidace-redukce účinky léků MeSH
- spektrofotometrie MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
3-aminobenzanthrone (3-ABA) is the metabolite of the carcinogenic air pollutant 3-nitrobenzanthrone (3-NBA). 3-ABA was investigated for its ability to induce cytochrome P450 1A1 (CYP1A1) and NAD(P)H:quinone oxidoreductase (NQO1) in kidney and lung of rats, and for the influence of such induction on DNA adduct formation by 3-ABA and 3-NBA. NQO1 is the enzyme that reduces 3-NBA to N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA) and CYP1A enzymes oxidize 3-ABA to the same intermediate. When activated by cytosolic and and/or microsomal fractions isolated from rat lung, the target organ for 3-NBA carcinogenicity, and kidney, both compounds generated the same DNA-adduct pattern, consisting of five adducts. When pulmonary cytosols isolated from rats that had been treated i.p. with 40 mg/kg bw of 3-ABA were incubated with 3-NBA, DNA adduct formation was up to 1.7-fold higher than in incubations with cytosols from control animals. This increase corresponded to an increase in protein level and enzymatic activity of NQO1. In contrast, no induction of NQO1 expression by 3-ABA treatment was found in the kidney. Incubations of 3-ABA with renal and pulmonary microsomes of 3-ABA-treated rats led to an increase of up to a 4.5-fold in DNA-adduct formation relative to controls. The stimulation of DNA-adduct formation correlated with a higher protein expression and activity of CYP1A1 induced by 3-ABA. These results show that by inducing lung and kidney CYP1A1 and NQO1, 3-ABA increases its own enzymatic activation as well as that of the environmental pollutant, 3-NBA, thereby enhancing the genotoxic and carcinogenic potential of both compounds.
- MeSH
- adukty DNA MeSH
- benz(a)anthraceny farmakologie metabolismus MeSH
- biotransformace MeSH
- cytochrom P-450 CYP1A1 metabolismus MeSH
- karcinogeny životního prostředí metabolismus MeSH
- krysa rodu rattus MeSH
- ledviny metabolismus účinky léků MeSH
- lidé MeSH
- mikrozomy enzymologie metabolismus účinky léků MeSH
- NAD(P)H dehydrogenasa (chinon) metabolismus MeSH
- plíce metabolismus účinky léků MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
BACKGROUND: Prostate specific membrane antigen (PSMA) is a type II transmembrane protein overexpressed in prostate cancer as well as in the neovasculature of several non-prostatic solid tumors. In addition to full-length PSMA, several splice variants exist in prostatic tissue. Notably, the N-terminally truncated PSMA variant, termed PSM', is prevalent in healthy prostate, and the ratio of PSMA/PSM' mRNA has been shown to correlate with cancer progression. The widely accepted hypothesis is that the PSM' protein is a translation product arising from the alternatively spliced PSM' mRNA. METHODS: Differential ultracentrifugation, cell surface biotinylation, Western blotting, and enzyme activity measurement were used to study the origin and localization of the PSMA/PSM' variants in prostatic (LNCaP; lymph-node carcinoma of the prostate) and non-prostatic (HEK293) cell lines. These experiments were further complemented by analysis of the N-glycosylation patterns of the PSMA/PSM' proteins and by site-directed mutagenesis. RESULTS: We identified PSM' protein expression in both the LNCaP cell line and a non-cancerous HEK293 human cell line transfected with a plasmid encoding full-length PSMA. Differential centrifugation revealed that PSM' is localized predominantly to the cytosol of both these cell lines and is proteolytically active. Furthermore, the PSM' protein is N-glycosylated by a mixture of high-mannose and complex type oligosaccharides and therefore trafficked beyond the cis-Golgi compartment. CONCLUSIONS: Our data suggest that the PSM' protein is likely not generated by alternative splicing of the PSMA gene but by different mechanism, probably via an endoproteolytic cleavage of the full-length PSMA.
- MeSH
- adenokarcinom metabolismus patologie MeSH
- buněčné linie MeSH
- financování organizované MeSH
- glykosylace MeSH
- ledviny cytologie embryologie metabolismus MeSH
- lidé MeSH
- lyzozomy metabolismus MeSH
- mikrozomy metabolismus MeSH
- místa sestřihu RNA genetika MeSH
- mitochondrie metabolismus MeSH
- nádorové buněčné linie MeSH
- nádory prostaty metabolismus patologie MeSH
- prostatický specifický antigen genetika chemie metabolismus MeSH
- transfekce MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- MeSH
- abdominální obezita metabolismus MeSH
- biomedicínský výzkum MeSH
- dyslipidemie genetika metabolismus MeSH
- financování organizované MeSH
- genetická predispozice k nemoci genetika MeSH
- genotyp MeSH
- inzulinová rezistence genetika imunologie MeSH
- lidé MeSH
- metabolický syndrom * genetika metabolismus MeSH
- mikrozomy metabolismus MeSH
- polymorfismus genetický * genetika imunologie MeSH
- rizikové faktory MeSH
- statistika jako téma MeSH
- transportní proteiny genetika metabolismus MeSH
- Check Tag
- lidé MeSH
