Physiology-based pharmacokinetic modeling suggests that rifabutin can out-balance P-glycoprotein (P-gp) induction by concurrent P-gp inhibition. However, clinical or experimental evidence for this Janus-faced rifabutin effect is missing. Consequently, LS180 cells were exposed to a moderately (2 μM) and strongly (10 μM) P-gp-inducing concentration of rifampicin or rifabutin for 6 days. Cellular accumulation of the fluorescent P-gp substrate rhodamine 123 was evaluated using flow cytometry, either without (induction only) or with adding rifamycin drug to the cells during the rhodamine 123 efflux phase (induction + potential inhibition). Rhodamine 123 accumulation was decreased similarly by both drugs after 6-day exposure (2 μM: 55% residual fluorescence compared to non-induced cells, P < 0.01; 10 μM: 30% residual fluorescence compared to non-induced cells, P < 0.001), indicating P-gp induction. Rhodamine 123 influx transporters mRNA expressions were not affected, excluding off-target effects. Acute re-exposure to rifabutin, however, considerably re-increased rhodamine 123 accumulation (2 μM induction: re-increase by 55%, P < 0.01; 10 μM induction: 49% re-increase, P < 0.001), suggesting P-gp inhibition. In contrast, rifampicin only had weak effects (2 μM induction: no re-increase; 10 μM induction: 16% re-increase; P < 0.05). Molecular docking analysis eventually revealed that rifabutin has a higher binding affinity to the inhibitor binding site of P-gp than rifampicin (ΔG (kcal/mol) = -11.5 vs -5.3). Together, this study demonstrates that rifabutin can at least partly mask P-gp induction by P-gp inhibition, mediated by high affinity binding to the inhibitory site of P-gp.
- MeSH
- ABC transportéry MeSH
- antitumorózní látky aplikace a dávkování terapeutické užití MeSH
- cytostatické látky aplikace a dávkování terapeutické užití MeSH
- doxorubicin aplikace a dávkování terapeutické užití MeSH
- geny MDR MeSH
- inhibitory HIV-proteasy farmakologie terapeutické užití MeSH
- inhibitory proteas farmakologie terapeutické užití MeSH
- lidé MeSH
- Lopinavir aplikace a dávkování terapeutické užití MeSH
- mnohočetná léková rezistence * účinky léků MeSH
- nádory farmakoterapie MeSH
- nanočásticový lékový transportní systém MeSH
- P-glykoprotein metabolismus účinky léků MeSH
- transkripční faktor STAT3 metabolismus MeSH
- Check Tag
- lidé MeSH
BACKGROUND: Multidrug resistance is the major obstacle to cancer chemotherapy. Modulation of P-glycoprotein and drug combination approaches have been considered important strategies to overcome drug resistance. PURPOSE: Aiming at generating a small library of Amaryllidaceae-type alkaloids to overcome drug resistance, two major alkaloids, isolated from Pancratium maritimum, lycorine (1), and 2α-10bα-dihydroxy-9-O-demethylhomolycorine (2), were derivatized, giving rise to nineteen derivatives (3 - 21). METHODS: The main chemical transformation of lycorine resulted from the cleavage of ring E of the diacetylated lycorine derivative (3) to obtain compounds that have carbamate and amine functions (5 - 16), while acylation of compound 2 provided derivatives 17 - 21. Compounds 1 - 21 were evaluated for their effects on cytotoxicity, and drug resistance reversal, using resistant human ovarian carcinoma cells (HOC/ADR), overexpressing P-glycoprotein (P-gp/ABCB1), as model. RESULTS: Excluding lycorine (1) (IC50 values of 1.2- 2.5 μM), the compounds were not cytotoxic or showed moderate/weak cytotoxicity. Chemo-sensitization assays were performed by studying the in vitro interaction between the compounds and the anticancer drug doxorubicin. Most of the compounds have shown synergistic interactions with doxorubicin. Compounds 5, 6, 9 - 14, bearing both carbamate and aromatic amine moieties, were found to have the highest sensitization rate, reducing the dose of doxorubicin 5-35 times, highlighting their potential to reverse drug resistance in combination chemotherapy. Selected compounds (4 - 6, 9 - 14, and 21), able of re-sensitizing resistant cancer cells, were further evaluated as P-gp inhibitors. Compound 11, which has a para‐methoxy-N-methylbenzylamine moiety, was the strongest inhibitor. In the ATPase assay, compounds 9-11 and 13 behaved as verapamil, suggesting competitive inhibition of P-gp. At the same time, none of these compounds affected P-gp expression at the mRNA or protein level. CONCLUSIONS: This study provided evidence of the potential of Amaryllidaceae alkaloids as lead candidates for the development of MDR reversal agents.
- MeSH
- adenokarcinom * MeSH
- alkaloidy amarylkovitých * farmakologie MeSH
- alkaloidy * farmakologie MeSH
- antitumorózní látky * farmakologie MeSH
- chemorezistence MeSH
- doxorubicin farmakologie MeSH
- fenantridiny * MeSH
- karbamáty farmakologie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- P-glykoprotein metabolismus MeSH
- P-glykoproteiny metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The placenta plays a critical role in maternal-fetal nutrient transport and fetal protection against drugs. Creating physiological in vitro models to study these processes is crucial, but technically challenging. This study introduces an efficient cell model that mimics the human placental barrier using co-cultures of primary trophoblasts and primary human umbilical vein endothelial cells (HUVEC) on a Transwell®-based system. Monolayer formation was examined over 7 days by determining transepithelial electrical resistance (TEER), permeability of Lucifer yellow (LY) and inulin, localization of transport proteins at the trophoblast membrane (immunofluorescence), and syncytialization markers (RT-qPCR/ELISA). We analysed diffusion-based (caffeine/antipyrine) and transport-based (leucine/Rhodamine-123) processes to study the transfer of physiologically relevant compounds. The latter relies on the adequate localization and function of the amino-acid transporter LAT1 and the drug transporter P-glycoprotein (P-gp) which were studied by immunofluorescence microscopy and application of respective inhibitors (2-Amino-2-norbornanecarboxylic acid (BCH) for LAT1; cyclosporine-A for P-gp). The formation of functional monolayer(s) was confirmed by increasing TEER values, low LY transfer rates, minimal inulin leakage, and appropriate expression/release of syncytialization markers. These results were supported by microscopic monitoring of monolayer formation. LAT1 was identified on the apical and basal sides of the trophoblast monolayer, while P-gp was apically localized. Transport assays confirmed the inhibition of LAT1 by BCH, reducing both intracellular leucine levels and leucine transport to the basal compartment. Inhibiting P-gp with cyclosporine-A increased intracellular Rhodamine-123 concentrations. Our in vitro model mimics key aspects of the human placental barrier. It represents a powerful tool to study nutrient and drug transport mechanisms across the placenta, assisting in evaluating safer pregnancy therapies.
- MeSH
- biologické modely MeSH
- biologický transport MeSH
- endoteliální buňky pupečníkové žíly (lidské) * metabolismus MeSH
- inulin metabolismus MeSH
- isochinoliny MeSH
- kokultivační techniky MeSH
- leucin metabolismus MeSH
- lidé MeSH
- maternofetální výměna látek * MeSH
- P-glykoprotein metabolismus MeSH
- placenta * metabolismus MeSH
- rhodamin 123 metabolismus MeSH
- těhotenství MeSH
- trofoblasty * metabolismus MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND OBJECTIVE: The dual orexin receptor antagonist daridorexant was approved in 2022 for the treatment of insomnia at doses up to 50 mg once per night. This study aimed at investigating the effect of daridorexant 50 mg at steady state on the pharmacokinetics of dabigatran, the active moiety of dabigatran etexilate, and rosuvastatin, sensitive substrates of P-glycoprotein and breast cancer resistance protein, respectively. METHODS: This single-center, open-label, fixed-sequence study enrolled 24 healthy male subjects who were dosed orally with dabigatran etexilate 75 mg on days 1 (Treatment A1) and 9 (Treatment C1) as well as rosuvastatin 10 mg on days 3 (Treatment A2) and 11 (Treatment C2). On days 7-14, daridorexant (50 mg once daily) was administered. Blood samples for the pharmacokinetics of both substrates and the pharmacodynamics of dabigatran, i.e., two coagulation tests, were collected and safety assessments performed. Noncompartmental pharmacokinetic parameters and pharmacodynamic variables were evaluated with geometric mean ratios and 90% confidence intervals of Treatment C1/C2 versus A1/A2. RESULTS: Geometric mean ratios (90% confidence interval) of dabigatran maximum plasma concentration and area under the plasma concentration-time curve were 1.3 (1.0-1.7) and 1.4 (1.1-1.9), respectively, whereas the time to maximum plasma concentration and terminal half-life were comparable between treatments. Pharmacodynamic variables showed a similar pattern as dabigatran pharmacokinetics in both treatments. Rosuvastatin pharmacokinetics were unchanged upon concomitant daridorexant administration. All treatments were well tolerated. CONCLUSIONS: A mild inhibition of P-glycoprotein was observed after administration of daridorexant (50 mg once daily) at steady state, whereas breast cancer resistance protein was not affected. CLINICAL TRIAL REGISTRATION: NCT05480475; date of registration: 29 July, 2022.
- MeSH
- ABC transportér z rodiny G, člen 2 MeSH
- benzimidazoly MeSH
- dabigatran * škodlivé účinky MeSH
- lidé MeSH
- nádorové proteiny MeSH
- nádory prsu * MeSH
- P-glykoprotein MeSH
- plocha pod křivkou MeSH
- pyridiny škodlivé účinky MeSH
- rosuvastatin kalcium farmakologie MeSH
- zdraví dobrovolníci pro lékařské studie MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: We aimed to compare the effects of P-glycoprotein (ABCB1) on the intestinal uptake of tenofovir disoproxil fumarate (TDF), tenofovir alafenamide fumarate (TAF), and metabolites, tenofovir isoproxil monoester (TEM) and tenofovir (TFV), and to study the molecular mechanism of drug-drug interaction (DDI) between sofosbuvir (SOF) and TDF/TAF. METHODS: Bidirectional transport experiments in Caco-2 cells and accumulation studies in precision-cut intestinal slices prepared from the ileal segment of rodent (rPCIS) and human (hPCIS) intestines were performed. RESULTS: TDF and TAF were extensively metabolised but TAF exhibited greater stability. ABCB1 significantly reduced the intestinal transepithelial transfer and uptake of the TFV(TDF) and TFV(TAF)-equivalents. However, TDF and TAF were absorbed more efficiently than TFV and TEM. SOF did not inhibit intestinal efflux of TDF and TAF or affect intestinal accumulation of TFV(TDF) and TFV(TAF)-equivalents but did significantly increase the proportion of absorbed TDF. CONCLUSIONS: TDF and TAF likely produce comparable concentrations of TFV-equivalents in the portal vein and the extent of permeation is reduced by the activity of ABCB1. DDI on ABCB1 can thus potentially affect TDF and TAF absorption. SOF does not inhibit ABCB1-mediated transport of TDF and TAF but does stabilise TDF, albeit without affecting the quantity of TFV(TDF)-equivalents crossing the intestinal barrier. Our data thus suggest that reported increases in the TFV plasma concentrations in patients treated with SOF and TDF result either from a DDI between SOF and TDF that does not involve ABCB1 or from a DDI involving another drug used in combination therapy.
- MeSH
- adenin metabolismus MeSH
- alanin MeSH
- Caco-2 buňky MeSH
- fumaráty MeSH
- HIV infekce * farmakoterapie MeSH
- látky proti HIV * MeSH
- lidé MeSH
- P-glykoprotein MeSH
- P-glykoproteiny MeSH
- sofosbuvir terapeutické užití MeSH
- tenofovir MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The nucleoside analog entecavir (ETV) is a first-line pharmacotherapy for chronic hepatitis B in adult and pediatric patients. However, due to insufficient data on placental transfer and its effects on pregnancy, ETV administration is not recommended for women after conception. To expand knowledge of safety, we focused on evaluating the contribution of nucleoside transporters (NBMPR sensitive ENTs and Na+ dependent CNTs) and efflux transporters, P-glycoprotein (ABCB1), breast cancer resistance protein (ABCG2), and multidrug resistance-associated transporter 2 (ABCC2), to the placental kinetics of ETV. We observed that NBMPR and nucleosides (adenosine and/or uridine) inhibited [3H]ETV uptake into BeWo cells, microvillous membrane vesicles, and fresh villous fragments prepared from the human term placenta, while Na+ depletion had no effect. Using a dual perfusion study in an open-circuit setup, we showed that maternal-to-fetal and fetal-to-maternal clearances of [3H]ETV in the rat term placenta were decreased by NBMPR and uridine. Net efflux ratios calculated for bidirectional transport studies performed in MDCKII cells expressing human ABCB1, ABCG2, or ABCC2 were close to the value of one. Consistently, no significant decrease in fetal perfusate was observed in the closed-circuit setup of dual perfusion studies, suggesting that active efflux does not significantly reduce maternal-to-fetal transport. In conclusion, ENTs (most likely ENT1), but not CNTs, ABCB1, ABCG2, and ABCC2, contribute significantly to the placental kinetics of ETV. Future studies should investigate the placental/fetal toxicity of ETV, the impact of drug-drug interactions on ENT1, and interindividual variability in ENT1 expression on the placental uptake and fetal exposure to ETV.
- MeSH
- ABC transportér z rodiny G, člen 2 metabolismus MeSH
- dítě MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- membránové transportní proteiny metabolismus MeSH
- nádorové proteiny metabolismus MeSH
- nádory prsu * metabolismus MeSH
- nukleosidy metabolismus farmakologie MeSH
- P-glykoprotein metabolismus MeSH
- P-glykoproteiny metabolismus MeSH
- placenta * metabolismus MeSH
- potkani Wistar MeSH
- protein spojený s mnohočetnou rezistencí k lékům 2 MeSH
- proteiny přenášející nukleosidy metabolismus farmakologie MeSH
- proteiny spojené s mnohočetnou rezistencí k lékům metabolismus MeSH
- těhotenství MeSH
- uridin MeSH
- zvířata MeSH
- Check Tag
- dítě MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Alisertib (MLN8237), a novel Aurora A kinase inhibitor, is currently being clinically tested in late-phase trials for the therapy of various malignancies. In the present work, we describe alisertib's potential to perpetrate pharmacokinetic drug-drug interactions (DDIs) and/or to act as an antagonist of multidrug resistance (MDR). In accumulation assays, alisertib potently inhibited ABCC1 transporter, but not ABCB1 or ABCG2. The results of molecular modeling suggested a bifunctional mechanism for interaction on ABCC1. In addition, alisertib was characterized as a low- to moderate-affinity inhibitor of recombinant CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2D6 isoenzymes, but without potential clinical relevance. Drug combination studies revealed the capability of alisertib to synergistically antagonize ABCC1-mediated resistance to daunorubicin. Although alisertib exhibited substrate characteristics toward ABCB1 transporter in monolayer transport assays, comparative proliferation studies showed lack of its MDR-victim behavior in cells overexpressing ABCB1 as well as ABCG2 and ABCC1. Lastly, alisertib did not affect the expression of ABCC1, ABCG2, ABCB1 transporters and CYP1A2, CYP3A4, CYP2B6 isozymes on mRNA level in various systemic and tumoral models. In conclusion, our study suggests that alisertib is a drug candidate with negligible potential for perpetrating systemic pharmacokinetic DDIs on ABCB1, ABCG2 and cytochromes P450. In addition, we introduce alisertib as an effective dual-activity chemosensitizer whose MDR-antagonistic capacities are not impaired by efflux or effect on MDR phenotype. Our in vitro findings provide important pieces of information for clinicians when introducing alisertib into the clinical area.
- MeSH
- ABC transportér z rodiny G, člen 2 genetika metabolismus MeSH
- azepiny farmakokinetika farmakologie MeSH
- buněčné linie MeSH
- katalytická doména MeSH
- konformace proteinů MeSH
- lékové interakce MeSH
- lidé MeSH
- molekulární modely MeSH
- P-glykoprotein genetika metabolismus MeSH
- proteiny spojené s mnohočetnou rezistencí k lékům antagonisté a inhibitory MeSH
- psi MeSH
- pyrimidiny farmakokinetika farmakologie MeSH
- regulace genové exprese účinky léků MeSH
- simulace molekulového dockingu MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Dabrafenib is a BRAF inhibitor used in combination treatment of malignant melanoma and non-small cell lung carcinoma. In this study, we aimed to characterize its interactions with cytochrome P450 (CYP) isoenzymes and ATP-binding cassette (ABC) efflux transporters that have critical impact on the pharmacokinetics of drugs and play a role in drug resistance development. Using accumulation assays, we showed that dabrafenib inhibited ABCG2 and, less potently, ABCB1 transporter. We also confirmed dabrafenib as a CYP2C8, CYP2C9, CYP3A4, and CYP3A5 inhibitor. Importantly, inhibition of ABCG2 and CYP3A4 by dabrafenib led to the potentiation of cytotoxic effects of mitoxantrone and docetaxel toward respective resistant cell lines in drug combination studies. On the contrary, the synergistic effect was not consistently observed in ABCB1-expressing models. We further demonstrated that mRNA levels of ABCB1, ABCG2, ABCC1, and CYP3A4 were increased after 24 h and 48 h exposure to dabrafenib. Overall, our data confirm dabrafenib as a drug frequently and potently interacting with ABC transporters and CYP isoenzymes. This feature should be addressed with caution when administering dabrafenib to patients with polypharmacy but also could be utilized advantageously when designing new dabrafenib-containing drug combinations to improve the therapeutic outcome in drug-resistant cancer.
- MeSH
- ABC transportér z rodiny G, člen 2 antagonisté a inhibitory genetika metabolismus MeSH
- antitumorózní látky aplikace a dávkování farmakologie MeSH
- buňky MDCK MeSH
- cytochrom P-450 CYP3A genetika metabolismus MeSH
- daunomycin aplikace a dávkování farmakologie MeSH
- imidazoly aplikace a dávkování farmakokinetika MeSH
- inhibitory cytochromu P450 aplikace a dávkování farmakologie MeSH
- kombinovaná farmakoterapie MeSH
- lidé MeSH
- messenger RNA genetika metabolismus MeSH
- mitoxantron aplikace a dávkování farmakologie MeSH
- nádorové buněčné linie MeSH
- oximy aplikace a dávkování farmakokinetika MeSH
- P-glykoprotein antagonisté a inhibitory genetika metabolismus MeSH
- psi MeSH
- regulace genové exprese účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Anticancer therapy by anthracyclines often leads to the development of multidrug resistance (MDR), with subsequent treatment failure. Thiosemicarbazones have been previously suggested as suitable anthracycline partners due to their ability to overcome drug resistance through dual Pgp-dependent cytotoxicity-inducing effects. Here, we focused on combining anthracyclines (doxorubicin, daunorubicin, and mitoxantrone) and two thiosemicarbazones (DpC and Dp44mT) for treating cell types derived from the most frequent pediatric solid tumors. Our results showed synergistic effects for all combinations of treatments in all tested cell types. Nevertheless, further experiments revealed that this synergism was independent of Pgp expression but rather resulted from impaired DNA repair control leading to cell death via mitotic catastrophe. The downregulation of checkpoint kinase 1 (CHEK1) expression by thiosemicarbazones and the ability of both types of agents to induce double-strand breaks in DNA may explain the Pgp-independent synergism between anthracyclines and thiosemicarbazones. Moreover, the concomitant application of these agents was found to be the most efficient approach, achieving the strongest synergistic effect with lower concentrations of these drugs. Overall, our study identified a new mechanism that offers an avenue for combining thiosemicarbazones with anthracyclines to treat tumors regardless the Pgp status.
- MeSH
- antibiotika antitumorózní MeSH
- antracykliny * farmakologie MeSH
- checkpoint kinasa 1 metabolismus MeSH
- dítě MeSH
- doxorubicin metabolismus farmakologie MeSH
- inhibitory topoisomerasy II MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- P-glykoprotein metabolismus MeSH
- poškození DNA MeSH
- thiosemikarbazony * farmakologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
