This study describes the discovery of novel prodrugs bearing tyrosine derivatives instead of the phenol moiety present in FDA-approved tenofovir alafenamide fumarate (TAF). The synthesis was optimized to afford diastereomeric mixtures of novel prodrugs in one pot (yields up to 86%), and the epimers were resolved using a chiral HPLC column into fast-eluting and slow-eluting epimers. In human lymphocytes, the most efficient tyrosine-based prodrug reached a single-digit picomolar EC50 value against HIV-1 and nearly 300-fold higher selectivity index (SI) compared to TAF. In human hepatocytes, the most efficient prodrugs exhibited subnanomolar EC50 values for HBV and up to 26-fold higher SI compared to TAF. Metabolic studies demonstrated markedly higher cellular uptake of the prodrugs and substantially higher levels of released tenofovir inside the cells compared to TAF. These promising results provide a strong foundation for further evaluation of the reported prodrugs and their potential utility in the development of highly potent antivirals.
- MeSH
- amidy chemie MeSH
- antivirové látky chemie farmakologie MeSH
- fenol chemie MeSH
- hepatocyty virologie MeSH
- HIV-1 účinky léků MeSH
- kyseliny fosforečné chemie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- objevování léků * MeSH
- prekurzory léčiv chemie farmakologie MeSH
- stereoizomerie MeSH
- tenofovir chemie farmakologie MeSH
- tyrosin chemie MeSH
- virus hepatitidy B účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The new screening method for rapid evaluation of major phenolic compounds in apples has been developed. Suitability of coupling HPLC/UHPLC separation with the diode-array detection and universal charged aerosol detection with respect to the presence of interfering substances was tested. Characteristics of both detection techniques were compared and method linearity, limits of detection and quantitation, and selectivity of them determined. Student t-test based on slopes of calibration plots was applied for the detailed comparison. The diode-array detection provided the best results regarding sensitivity and selectivity of the developed method in terms of evaluation of phenolics profiles. The response of the charged aerosol detector was negatively affected by co-eluting substances during rapid-screening analyses. Coulometric detection was used for advanced characterization of extracts in terms of antioxidant content and strength to obtain more complex information concerning sample composition. This detection also allowed evaluation of unidentified compounds with antioxidant activity. HPLC/UHPLC separation using a combination of diode-array and coulometric detectors thus represented the best approach enabling quick, yet complex characterization of bioactive compounds in apples.
- MeSH
- aerosoly chemie MeSH
- antioxidancia chemie MeSH
- chromatografie metody MeSH
- elektrochemie metody MeSH
- fenol chemie MeSH
- fenoly analýza MeSH
- kalibrace MeSH
- limita detekce MeSH
- Malus metabolismus MeSH
- potravinářská technologie MeSH
- reprodukovatelnost výsledků MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Publikační typ
- časopisecké články MeSH
Protein phosphorylation is the most abundant and best studied protein posttranslational modification, dedicated to the regulation of protein function and subcellular localization as well as to protein-protein interactions. Identification and quantitation of the dynamic, conditional protein phosphorylation can be achieved by either metabolic labeling of the protein of interest with (32)P-labeled ATP followed by autoradiographic analysis, the use of specific monoclonal or polyclonal antibodies against the phosphorylated protein species and finally by phosphoproteome delineation using mass spectrometry.Hereby we present a fourth alternative which relies on the enforced-affinity-based-electrophoretic separation of phosphorylated from non-phosphorylated protein species by standard SDS-PAGE systems co-polymerized with Phos-Tag™ and Mn(2+) or Zn(2+) cations. Phosphate groups of phosphorylated Ser, Thr, and Tyr residues form complexes with Mn(2+) and Zn(2+) cations with polyacrylamide immobilized Phos-Tag™. Following appropriate treatment of the gels, separated proteins can be quantitatively transferred to PVDF or nitrocellulose membranes and probed with common-not phosphorylation state specific-antibodies and delineate the occurrence of a certain phosphoprotein species against its non-phosphorylated counterpart.
- MeSH
- akrylamid chemie MeSH
- Arabidopsis enzymologie růst a vývoj MeSH
- bakteriofág lambda enzymologie MeSH
- elektroforéza v polyakrylamidovém gelu metody MeSH
- fenol chemie MeSH
- fosfatasy metabolismus MeSH
- fosfoproteiny izolace a purifikace metabolismus MeSH
- fosforylace MeSH
- kultivační techniky MeSH
- membrány umělé MeSH
- mitogenem aktivované proteinkinasy izolace a purifikace metabolismus MeSH
- polyvinyly chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Candida tropicalis yeast is a microorganism that possesses high tolerance for phenol and shows strong phenol degrading activity. This yeast is capable of utilizing phenol as the sole carbon and energy source. While the enzyme participating on the first step of phenol biodegradation, NADPH-dependent phenol hydroxylase, has already been characterized, information on the enzyme participating in the second step of its degradation, catechol 1,2-dioxygenase, is scarce. The development of the procedure suitable for catechol 1,2-dioxygenase isolation and partial characterization of this enzyme are the aims of this study. METHODS: Combination of chromatography on DEAE-Sepharose and gel-permeation chromatography on Sephadex G-100 was used for isolation of cytosolic catechol 1,2-dioxygenase from C. tropicalis yeast. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel chromatography on Sephadex G-100 were used to evaluate the molecular mass of the enzyme. The enzyme activity was followed by HPLC (catechol consumption and/or cis,cis-muconic acid formation). RESULTS: Using the isolation procedure consisting of chromatography and re-chromatography on a column of DEAE-Sepharose and gel filtration on Sephadex G-100, catechol 1,2-dioxygenase was purified from C. tropicalis cytosol to homogeneity. Catechol 1,2-dioxygenase was found to be a homodimer with a subunit molecular mass of 30000 +/- 5000. The enzyme oxidized catechol producing cis,cis-muconic acid. The optimal temperature and pH were 30 degrees C and 7.7, respectively. CONCLUSIONS: The data are the first report showing the isolation of eukaryotic catechol 1,2-dioxygenase from C. tropicalis to homogeneity and its partial characterization.
- MeSH
- Candida tropicalis enzymologie metabolismus MeSH
- chromatografie MeSH
- cytosol chemie enzymologie metabolismus MeSH
- dextrany MeSH
- dimerizace MeSH
- elektroforéza v polyakrylamidovém gelu MeSH
- fenol chemie MeSH
- fungální proteiny chemie izolace a purifikace metabolismus MeSH
- gelová chromatografie MeSH
- katechol-1,2-dioxygenasa chemie izolace a purifikace metabolismus MeSH
- katecholy chemie metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- kyselina sorbová analogy a deriváty chemie metabolismus MeSH
- oxidace-redukce MeSH
- teplota MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this study, the UVA (photo)protective activity of the phenolic fraction of L. caerulea fruits (PFLC) was assessed in human keratinocytes HaCaT. The keratinocytes were pre- or post-treated with PFLC (1-250 mg/l) and exposed to UVA irradiation (10-30 J/cm(2)). The results showed that both pre- and post-treatment with PFLC significantly suppressed UVA-induced ROS production, which was also revealed as a decrease in intracellular lipid peroxidation and elevation of reduced glutathione. Protection was concentration-dependent with a maximum at 50 mg/l. These results suggest that PFLC attenuates UVA-induced oxidative stress by reduction of ROS generation and ROS-mediated damage. For this reason, PFLC has potentially skin-protective functions against the deleterious effects of sunlight.
- MeSH
- fenol chemie MeSH
- fytoterapie MeSH
- glutathion metabolismus účinky léků účinky záření MeSH
- keratinocyty patologie účinky léků účinky záření MeSH
- kůže patologie účinky léků účinky záření MeSH
- lidé MeSH
- Lonicera MeSH
- oxidační stres účinky léků účinky záření MeSH
- peroxidace lipidů účinky léků účinky záření MeSH
- radiační poranění prevence a kontrola MeSH
- reaktivní formy kyslíku antagonisté a inhibitory účinky záření MeSH
- rostlinné extrakty farmakologie chemická syntéza MeSH
- scavengery volných radikálů metabolismus MeSH
- transformované buněčné linie MeSH
- ultrafialové záření škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- randomizované kontrolované studie MeSH