Myricetin (MYR) and ampelopsin (AMP, or dihydromyricetin) are flavonoid aglycones found in certain plants and dietary supplements. During the presystemic biotransformation of flavonoids, mainly sulfate and glucuronide derivatives are produced, which are the dominant metabolites in the circulation. In this study, we tested the interactions of MYR, myricetin-3'-O-sulfate (M3'S), AMP, and ampelopsin-4'-O-sulfate (A4'S) with human serum albumin (HSA), cytochrome P450 enzymes (CYPs), and organic anion-transporting polypeptides (OATPs) using in vitro models, including the recently developed method for measuring flavonoid levels in living cells. M3'S and MYR bound to albumin with high affinity, and they showed moderate displacing effects versus the Site I marker warfarin. MYR, M3'S, AMP, and A4'S exerted no or only minor inhibitory effects on CYP2C9, CYP2C19, and CYP3A4 enzymes. M3'S and MYR caused considerable inhibitory actions on OATP1B1 at low micromolar concentrations (IC50 = 1.7 and 6.4 μM, respectively), while even their nanomolar levels resulted in strong inhibitory effects on OATP2B1 (IC50 = 0.3 and 0.4 μM, respectively). In addition, M3'S proved to be a substrate of OATP1B1 and OATP2B1. These results suggest that MYR-containing dietary supplements may affect the OATP-mediated transport of certain drugs, and OATPs are involved in the tissue uptake of M3'S.
- Klíčová slova
- CYP enzymes, OATP transporters, ampelopsin, human serum albumin, myricetin,
- MeSH
- cytochrom P-450 CYP3A metabolismus MeSH
- cytochrom P450 CYP2C9 metabolismus MeSH
- flavonoidy * farmakologie MeSH
- flavonoly farmakologie MeSH
- lidé MeSH
- polypeptid C přenášející organické anionty * metabolismus MeSH
- přenašeče organických aniontů * metabolismus MeSH
- sérový albumin metabolismus MeSH
- sírany metabolismus MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- ampelopsin MeSH Prohlížeč
- CYP3A4 protein, human MeSH Prohlížeč
- cytochrom P-450 CYP3A MeSH
- cytochrom P450 CYP2C9 MeSH
- dihydromyricetin MeSH Prohlížeč
- flavonoidy * MeSH
- flavonoly MeSH
- myricetin MeSH Prohlížeč
- polypeptid C přenášející organické anionty * MeSH
- přenašeče organických aniontů * MeSH
- sérový albumin MeSH
- sírany MeSH
- SLCO1B1 protein, human MeSH Prohlížeč
- SLCO2B1 protein, human MeSH Prohlížeč
- systém (enzymů) cytochromů P-450 MeSH
Organic anion transporting polypeptides (OATPs), OATP1B1 and OATP2B1 are membrane proteins mediating the cellular uptake of chemically diverse organic compounds. OATP1B1 is exclusively expressed in hepatocytes and plays a key role in hepatic detoxification. The ubiquitously expressed OATP2B1 promotes the intestinal absorption of orally administered drugs. Flavonoids are widely found in foods and beverages, and many of them can inhibit OATP function, resulting in food-drug interactions. In our previous work, we have shown that not only luteolin (LUT) and quercetin (Q), but also some of their metabolites can inhibit OATP1B1 and OATP2B1 activity. However, data about the potential direct transport of these flavonoids by OATPs have been incomplete. Hence, in the current study, we developed a simple, fluorescence-based method for the measurement of intracellular flavonoid levels. The method applies a cell-permeable small molecule (2-aminoethyl diphenylborinate, 2-APB), that, upon forming a complex with flavonoids, results in their fluorescence enhancement. This way the direct uptake of LUT and Q, and also their metabolites' could be investigated both by confocal microscopy and in a fluorescence plate reader in living cells. With this approach we identified quercetin-3'-O-sulfate, luteolin-3'-O-glucuronide, luteolin-7-O-glucuronide and luteolin-3'-O-sulfate as substrates of both OATP1B1 and OATP2B1. Our results highlight that OATP1B1 and OATP2B1 can be key participants in the transmembrane movement of LUT and Q conjugates with otherwise low cell permeability. In addition, the novel method developed in this study can be a good completion to existing fluorescence-based assays to investigate OATP function.
- Klíčová slova
- Fluorescence enhancer, Fluorescence-based direct transport, Luteolin metabolite, Organic anion transporting polypeptide, Quercetin metabolite,
- Publikační typ
- časopisecké články MeSH
Luteolin and naringenin are flavonoids found in various foods/beverages and present in certain dietary supplements. After a high intake of these flavonoids, their sulfate and glucuronide conjugates reach micromolar concentrations in the bloodstream. Some pharmacokinetic interactions of luteolin and naringenin have been investigated in previous studies; however, only limited data are available in regard to their metabolites. In this study, we aimed to investigate the interactions of the sulfate and glucuronic acid conjugates of luteolin and naringenin with human serum albumin, cytochrome P450 (CYP2C9, 2C19, and 3A4) enzymes, and organic anion transporting polypeptide (OATP1B1 and OATP2B1) transporters. Our main findings are as follows: (1) Sulfate conjugates formed more stable complexes with albumin than the parent flavonoids. (2) Luteolin and naringenin conjugates showed no or only weak inhibitory action on the CYP enzymes examined. (3) Certain conjugates of luteolin and naringenin are potent inhibitors of OATP1B1 and/or OATP2B1 enzymes. (4) Conjugated metabolites of luteolin and naringenin may play an important role in the pharmacokinetic interactions of these flavonoids.
- Klíčová slova
- Cytochrome P450 enzymes, Human serum albumin, Luteolin, Naringenin, OATP transporters, Sulfate/glucuronide metabolites,
- MeSH
- cytochrom P-450 CYP3A * metabolismus MeSH
- cytochrom P450 CYP2C19 metabolismus MeSH
- cytochrom P450 CYP2C9 metabolismus MeSH
- flavonoidy farmakologie MeSH
- glukuronidy MeSH
- lidé MeSH
- lidský sérový albumin metabolismus MeSH
- luteolin farmakologie MeSH
- přenašeče organických aniontů * metabolismus MeSH
- sírany metabolismus MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- CYP2C19 protein, human MeSH Prohlížeč
- CYP2C9 protein, human MeSH Prohlížeč
- CYP3A4 protein, human MeSH Prohlížeč
- cytochrom P-450 CYP3A * MeSH
- cytochrom P450 CYP2C19 MeSH
- cytochrom P450 CYP2C9 MeSH
- flavonoidy MeSH
- glukuronidy MeSH
- lidský sérový albumin MeSH
- luteolin MeSH
- přenašeče organických aniontů * MeSH
- sírany MeSH
- systém (enzymů) cytochromů P-450 MeSH
Special attention is required when pharmacological treatment is indicated for a pregnant woman. P-glycoprotein (MDR1) is a well-known transporter localized in the maternal blood-facing apical membrane of placental syncytiotrophoblast and is considered to play an important role in protecting the developing fetus. Maraviroc, a MDR1 substrate that is registered for treatment of HIV infection, shows a low toxicity profile, suggesting favorable tolerability also if administered to pregnant women. Nevertheless, there is only poor understanding to date regarding the extent to which it permeates across the placental barrier and what are the transport mechanisms involved. Endeavoring to clarify the passage of maraviroc across placenta, we used in this study the method of closed-circuit perfusion of maraviroc across human placental cotyledon. The data obtained confirmed slight involvement of MDR1, but they also suggest possible interaction with other transport system(s) working in the opposite direction from that of MDR1. Complementary in vitro studies, including cellular experiments on choriocarcinoma BeWo cells as well as transporter-overexpressing MDCKII and A431 cell lines and accumulation in placental fresh villous fragments, revealed maraviroc transport by MRP1, OATP1A2, and OATP1B3 transporters. Based on mRNA expression data in the placental tissue, isolated trophoblasts, and fetal endothelial cells, especially MRP1 and OATP1A2 seem to play a crucial role in cooperatively driving maraviroc into placental tissue. By the example of maraviroc, we show here the important interplay of transporters in placental drug handling and its possibility to overcome the MDR1-mediated efflux.
- Klíčová slova
- Drug transporters, Drug–drug interactions, MRP1, Maraviroc, OATP, Placenta,
- MeSH
- akridiny farmakologie MeSH
- buňky MDCK MeSH
- látky proti HIV krev metabolismus farmakologie MeSH
- lékové interakce MeSH
- lidé MeSH
- maravirok krev metabolismus MeSH
- nádorové buněčné linie MeSH
- P-glykoproteiny antagonisté a inhibitory genetika metabolismus MeSH
- perfuze MeSH
- placenta účinky léků metabolismus MeSH
- placentární oběh MeSH
- přenašeče organických aniontů antagonisté a inhibitory genetika metabolismus MeSH
- protein OATP1B3 antagonisté a inhibitory genetika metabolismus MeSH
- proteiny spojené s mnohočetnou rezistencí k lékům genetika metabolismus MeSH
- psi MeSH
- regulace genové exprese MeSH
- ritonavir farmakologie MeSH
- těhotenství MeSH
- tetrahydroisochinoliny farmakologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- ABCB1 protein, human MeSH Prohlížeč
- akridiny MeSH
- Elacridar MeSH Prohlížeč
- látky proti HIV MeSH
- maravirok MeSH
- multidrug resistance-associated protein 1 MeSH Prohlížeč
- P-glykoproteiny MeSH
- přenašeče organických aniontů MeSH
- protein OATP1B3 MeSH
- proteiny spojené s mnohočetnou rezistencí k lékům MeSH
- ritonavir MeSH
- SLCO1A2 protein, human MeSH Prohlížeč
- SLCO1B3 protein, human MeSH Prohlížeč
- tetrahydroisochinoliny MeSH
