The aryl hydrocarbon receptor (AhR) is a cytosolic ligand-activated transcription factor integral to various physiological and pathological processes. Among its diverse ligands, indole-based compounds have garnered attention due to their significant biological activity and potential therapeutic applications. This study explores the activation of AhR by structurally diverse halogenated indoles. We evaluated the transcriptional activity of AhR and cell viability in the human LS174T-AhR-luc reporter cell line. Among the tested compounds, 4-FI, 7-FI, 6-BrI, 7-BrI, 6-Cl-2-ox, 5-Br-2-ox, and 6-Br-2-ox activated AhR in a concentration-dependent manner, displaying high efficacy and potency. Molecular docking analysis revealed moderate binding affinities of these compounds to the PAS-B domain of AhR, corroborated by competitive radioligand binding assays. Functional assays showed that halogenated indoles induce the formation of AhR-ARNT heterodimer and enhance the binding of the AhR to the CYP1A1 promoter. Additionally, 4-FI and 7-FI exhibited anti-inflammatory properties in Caco-2 cell models, highlighting their potential for therapeutic applications. This study underscores the significance of the type and position of halogen moiety in indole scaffold, suggesting their potential as candidates for developing therapeutics drugs to treat conditions such as inflammatory bowel disease via AhR activation.

• MeSH
• cytochrom P-450 CYP1A1 metabolismus   MeSH
• halogenace MeSH
• indoly * chemie   farmakologie   MeSH
• lidé MeSH
• molekulární struktura MeSH
• receptory aromatických uhlovodíků * metabolismus   chemie   MeSH
• simulace molekulového dockingu * MeSH
• transkripční faktory bHLH MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

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.

• 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

Lenvatinib is an orally effective tyrosine kinase inhibitor used to treat several types of tumors, including progressive, radioiodine-refractory differentiated thyroid cancer and advanced renal cell carcinoma. Although this drug is increasingly used in therapy, its metabolism and effects on the organism are still not described in detail. Using the rat as an experimental animal model, this study aimed to investigate the metabolism of lenvatinib by rat microsomal enzymes and cytochrome P450 (CYPs) enzymes recombinantly expressed in SupersomesTMin vitro and to assess the effect of lenvatinib on rat CYP expression in vivo. Two metabolites, O-desmethyl lenvatinib, and lenvatinib N-oxide, were produced by rat CYPs in vitro. CYP2A1 and 2C12 were found to be the most effective in forming O-desmethyl lenvatinib, while CYP3A2 was found to primarily form lenvatinib N-oxide. The administration of lenvatinib to rats caused changes in the expression of mRNA and protein, as well as the activity of various CYPs, particularly in an increase in CYP1A1. Thus, the administration of lenvatinib to rats has an impact on the level of CYPs.

• MeSH
• chinoliny * farmakologie   MeSH
• fenylmočovinové sloučeniny * farmakologie   MeSH
• inhibitory proteinkinas * farmakologie   MeSH
• inhibitory tyrosinkinasy MeSH
• jaterní mikrozomy účinky léků   MeSH
• játra * účinky léků   metabolismus   MeSH
• krysa rodu rattus MeSH
• messenger RNA metabolismus   genetika   MeSH
• oxidace-redukce * účinky léků   MeSH
• potkani Sprague-Dawley MeSH
• systém (enzymů) cytochromů P-450 * metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Rifampicin is a model ligand of the pregnane X receptor (PXR), the nuclear receptor involved in the regulation of cytochrome P450 3A4 (CYP3A4). Rifampicin forms several degradation products and metabolites of which 25-desacetylrifampicin is the most abundant in vivo. Here, we aimed to study both the stability and metabolism of rifampicin in media and 2D and 3D primary human hepatocytes (PHHs). Additionally, we analyzed interactions of rifampicin derivatives with PXR. We described that rifampicin gradually degrades by more than 50 % in the medium partly into quinone over 72 h. We observed 25-desacetylrifampicin in 2D PHHs but not in 3D PHHs. Contrary, rifampicin was converted into quinone in a one-direction process in media of 3D PHHs. The potency of rifampicin and its derivatives to activate human PXR was arranged as follows: 3-formylrifamycin SV > rifampicin quinone > rifampicin > rifampicin N-oxide > 25-desacetylrifampicin, respectively, but none activates mouse and rat PXR. The binding differences between rifampicin and 25-desacetylrifampicin were modeled in silico. Finally, we showed that overexpressed uptake organic anion transporting polypeptide 1B1 (OATP1B1) potentiated activation of PXR by rifampicin and rifampicin quinone, but overexpressed efflux multidrug resistance protein 1 (MDR1) decreased PXR activation by all derivatives.

• MeSH
• cytochrom P-450 CYP3A metabolismus   MeSH
• hepatocyty * metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• myši MeSH
• pregnanový X receptor * metabolismus   MeSH
• rifampin * farmakologie   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Polypragmazie, fenomén dnešní medicíny, přináší velké riziko vzniku lékových interakcí. Některé z nich mohou vést k závažným nežádoucím účinkům nebo selhání léčby, znalosti v této oblasti se dynamicky rozvíjejí. Farmakokinetické lékové interakce se mohou vyskytovat nejen při metabolizaci léčiv systémem izoenzymů cytochromu P450, ale i na úrovni transportérů, kterých je již popsána celá řada. Pro hodnocení jejich klinického významu je třeba se orientovat ve farmakodynamice a farmakokinetice léčiv, ale uvažovat i nad dalšími faktory, které dopad lékové interakce ovlivní. Lékař by měl znát běžně předepisovaná léčiva s vysokým interakčním potenciálem, mít povědomí o silných induktorech a inhibitorech CYP450 a také o možném vlivu genetického polymorfismu některých jeho izoforem. Neměl by se však spolehnout na interpretaci lékových interakcí pouze za využití dostupných interakčních databází. Žádný software zatím není schopen vyhodnocovat interakce komplexně a v kontextu konkrétního pacienta, jeho zdravotního stavu a komorbidit. Rovněž je třeba správně porozumět dostupným informacím a pozorováním z klinických studií a umět je převést do reálné praxe. S výhodou dnes již může lékař konzultovat problematiku lékových interakcí u konkrétního pacienta s klinickým farmaceutem nebo farmakologem. Tento článek shrnuje problematiku lékových interakcí, se zaměřením na ty méně intuitivní a s uvedením konkrétních příkladů z praxe.

Polypharmacy, a phenomenon of today’s medicine, brings a great risk of drug interactions. Some of them can lead to serious side effects or treatment failure, knowledge in this field is dramatically developing. Pharmacokinetic drug interactions can occur not only when drugs are metabolized by the cytochrome P450 isoenzyme system, but also at the level of transporters, a number of which have already been described. In order to assess their clinical significance, it is necessary to orient oneself in the pharmacodynamics and pharmacokinetics of drugs, but also to consider other factors that will influence the impact of drug interactions. The physician should be familiar with commonly prescribed drugs with a high interaction potential, be aware of strong inducers and inhibitors of CYP450, as well as the possible influence of genetic polymorphism of some of its isoforms. However, one should not rely on the interpretation of drug interactions only using available interaction databases. No software is yet capable of evaluating interactions comprehensively and in the context of a specific patient, their health status and comorbidities. Also, the information available from clinical studies and observations needs to be properly understood and translated into real practice. Nowadays, it is a great advantage a doctor can consult with a clinical pharmacist or pharmacologist on the issue of drug interactions in a specific patient. This article summarizes the issue of drug interactions, focusing on the less intuitive ones, with examples from practice.

• MeSH
• lékové interakce * MeSH
• lidé MeSH
• polypharmacy * MeSH
• systém (enzymů) cytochromů P-450 metabolismus   účinky léků   MeSH
• systémy cílené aplikace léků MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

Dietary exposure to aflatoxin B1 (AFB1) is harmful to the health and performance of domestic animals. The hepatic cytochrome P450s (CYPs), CYP1A1 and CYP2A6, are the primary enzymes responsible for the bioactivation of AFB1 to the highly toxic exo-AFB1-8,9-epoxide (AFBO) in chicks. However, the transcriptional regulation mechanism of these CYP genes in the liver of chicks in AFB1 metabolism remains unknown. Dual-luciferase reporter assay, bioinformatics and site-directed mutation results indicated that specificity protein 1 (SP1) and activator protein-1 (AP-1) motifs were located in the core region -1,063/-948, -606/-541 of the CYP1A1 promoter as well as -636/-595, -503/-462, -147/-1 of the CYP2A6 promoter. Furthermore, overexpression and decoy oligodeoxynucleotide technologies demonstrated that SP1 and AP-1 were pivotal transcriptional activators regulating the promoter activity of CYP1A1 and CYP2A6. Moreover, bioactivation of AFB1 to AFBO could be increased by upregulation of CYP1A1 and CYP2A6 expression, which was trans-activated owing to the upregulalion of AP-1, rather than SP1, stimulated by AFB1-induced reactive oxygen species. Additionally, nano-selenium could reduce ROS, downregulate AP-1 expression and then decrease the expression of CYP1A1 and CYP2A6, thus alleviating the toxicity of AFB1. In conclusion, AP-1 and SP1 played important roles in the transactivation of CYP1A1 and CYP2A6 expression and further bioactivated AFB1 to AFBO in chicken liver, which could provide novel targets for the remediation of aflatoxicosis in chicks.

• MeSH
• aflatoxin B1 * metabolismus   MeSH
• aktivace transkripce MeSH
• cytochrom P-450 CYP1A1 * genetika   metabolismus   MeSH
• cytochrom P450 CYP2A6 * metabolismus   genetika   MeSH
• játra * metabolismus   MeSH
• kur domácí * metabolismus   MeSH
• promotorové oblasti (genetika) * MeSH
• transkripční faktor AP-1 * metabolismus   genetika   MeSH
• transkripční faktor Sp1 * metabolismus   genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND 21-hydroxylase deficiency, an essential enzyme for glucocorticoid and mineralocorticoid synthesis, is the cause of congenital adrenal hyperplasia (CAH) in more than 95% of cases. It is an autosomal recessive disorder encoded by the CYP21A2 gene, categorized into classical forms, which encompass the salt-wasting (SW) and simple virilizing (SV) forms, as well as the nonclassical form (NC). The aim of medical treatment is to replace missing glucocorticoids and, if necessary, mineralocorticoids, while also reducing elevated adrenal androgens. CASE REPORT We present the case of a 42-year-old woman with CAH who discontinued therapy during adolescence and was admitted to hospital with fatigue, nausea, and severe abdominal pain. A CT scan showed an extreme enlargement of the adrenal glands. Laboratory tests revealed elevated levels of 17-hydroxyprogesterone and other adrenal androgens, along with normal plasma metanephrine levels. Decreased morning cortisol levels suggested partial adrenal insufficiency requiring glucocorticoid replacement therapy. Due to the development of several serious complications and clinical deterioration, the multidisciplinary team recommended bilateral removal of masses measuring 300×250×200 mm on the right side and 250×200×200 mm on the left side. Histological and immunochemical examination confirmed the presence of giant myelolipomas with adrenal cortex hyperplasia. CONCLUSIONS Adrenal tumors, particularly myelolipomas, have a higher prevalence in patients with CAH. Our case report provides further evidence of the suspected link between non-compliant CAH therapy and the development of myelolipomas, along with promotion of their pronounced growth.

• MeSH
• dospělí MeSH
• glukokortikoidy terapeutické užití   MeSH
• kongenitální adrenální hyperplazie * komplikace   diagnóza   genetika   MeSH
• lidé MeSH
• lipom * MeSH
• myelolipom * diagnóza   chirurgie   komplikace   MeSH
• nadledviny MeSH
• nádory nadledvin * komplikace   diagnóza   MeSH
• steroid-21-hydroxylasa genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

As compounds of natural origin enter human body, it is necessary to investigate their possible interactions with the metabolism of drugs and xenobiotics in general, namely with the cytochrome P450 (CYP) system. Phytic acid (myo-inositol hexaphosphoric acid, IP6) is mainly present in plants but is also an endogenous compound present in mammalian cells and tissues. It has been shown to exhibit protective effect in many pathological conditions. For this paper, its interaction with CYPs was studied using human liver microsomes, primary human hepatocytes, the HepG2 cell line, and molecular docking. Docking experiments and absorption spectra demonstrated the weak ability of IP6 to interact in the heme active site of CYP1A. Molecular docking suggested that IP6 preferentially binds to the protein surface, whereas binding to the active site of CYP1A2 was found to be less probable. Subsequently, we investigated the ability of IP6 to modulate the metabolism of xenobiotics for both the mRNA expression and enzymatic activity of CYP1A enzymes. Our findings revealed that IP6 can slightly modulate the mRNA levels and enzyme activity of CYP1A. However, thanks to the relatively weak interactions of IP6 with CYPs, the chances of the mechanisms of clinically important drug-drug interactions involving IP6 are low.

• MeSH
• kyselina fytová * MeSH
• lidé MeSH
• messenger RNA MeSH
• savci MeSH
• simulace molekulového dockingu MeSH
• systém (enzymů) cytochromů P-450 MeSH
• xenobiotika * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Microbiota plays a role in shaping the HPA-axis response to psychological stressors. To examine the role of microbiota in response to acute immune stressor, we stimulated the adaptive immune system by anti-CD3 antibody injection and investigated the expression of adrenal steroidogenic enzymes and profiling of plasma corticosteroids and their metabolites in specific pathogen-free (SPF) and germ-free (GF) mice. Using UHPLC-MS/MS, we showed that 4 hours after immune challenge the plasma levels of pregnenolone, progesterone, 11-deoxycorticosterone, corticosterone (CORT), 11-dehydroCORT and their 3α/β-, 5α-, and 20α-reduced metabolites were increased in SPF mice, but in their GF counterparts, only CORT was increased. Neither immune stress nor microbiota changed the mRNA and protein levels of enzymes of adrenal steroidogenesis. In contrast, immune stress resulted in downregulated expression of steroidogenic genes (Star, Cyp11a1, Hsd3b1, Hsd3b6) and upregulated expression of genes of the 3α-hydroxysteroid oxidoreductase pathway (Akr1c21, Dhrs9) in the testes of SPF mice. In the liver, immune stress downregulated the expression of genes encoding enzymes with 3β-hydroxysteroid dehydrogenase (HSD) (Hsd3b2, Hsd3b3, Hsd3b4, Hsd3b5), 3α-HSD (Akr1c14), 20α-HSD (Akr1c6, Hsd17b1, Hsd17b2) and 5α-reductase (Srd5a1) activities, except for Dhrs9, which was upregulated. In the colon, microbiota downregulated Cyp11a1 and modulated the response of Hsd11b1 and Hsd11b2 expression to immune stress. These data underline the role of microbiota in shaping the response to immune stressor. Microbiota modulates the stress-induced increase in C21 steroids, including those that are neuroactive that could play a role in alteration of HPA axis response to stress in GF animals.

• MeSH
• enzym štěpící postranní řetězce cholesterolu genetika   metabolismus   MeSH
• kortikosteron metabolismus   MeSH
• mikrobiota * MeSH
• myši MeSH
• steroidy metabolismus   MeSH
• systém hypofýza - nadledviny metabolismus   MeSH
• systém hypotalamus-hypofýza * metabolismus   MeSH
• tandemová hmotnostní spektrometrie MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Caffeine (CAF) ingestion improves performance in a broad range of exercise tasks. Nevertheless, the CAF-induced, dose-dependent effect on discipline-specific performance and cognitive functions in CrossFit/High-Intensity Functional Training (HIFT) has not been sufficiently investigated. The aim of this study was to evaluate the effect of acute supplementation of three different doses of CAF and placebo (PLA) on specific performance, reaction time (RTime), postural stability (PStab), heart rate (HR) and perceived exertion (RPE). METHODS: In a randomized double-blind placebo-controlled crossover design, acute pre-exercise supplementation with CAF (3, 6, or 9 mg/kg body mass (BM)) and PLA in 26 moderately trained CrossFit practitioners was examined. The study protocol involved five separate testing sessions using the Fight Gone Bad test (FGB) as the exercise performance evaluation and biochemical analyses, HR and RPE monitoring, as well as the assessment of RTime and PStab, with regard to CYP1A2 (rs762551) and ADORA2A (rs5751876) single nucleotide polymorphism (SNP). RESULTS: Supplementation of 6 mgCAF/kgBM induced clinically noticeable improvements in FGBTotal results, RTime and pre-exercise motor time. Nevertheless, there were no significant differences between any CAF doses and PLA in FGBTotal, HRmax, HRmean, RPE, pre/post-exercise RTime, PStab variables or pyruvate concentrations. Lactate concentration was higher (p < 0.05) before and after exercise in all CAF doses than in PLA. There was no effect of CYP1A2 or ADORA2A SNPs on performance. CONCLUSIONS: The dose-dependent effect of CAF supplementation appears to be limited to statistically nonsignificant but clinically considered changes on specific performance, RTime, PStab, RPE or HR. However, regarding practical CAF-induced performance implications in CrossFit/HIFT, 6 mgCAF/kgBM may be supposed as the most rational supplementation strategy.

• MeSH
• cytochrom P-450 CYP1A2 MeSH
• dvojitá slepá metoda MeSH
• klinické křížové studie MeSH
• kofein * farmakologie   MeSH
• kyselina mléčná MeSH
• lidé MeSH
• polyestery MeSH
• potravní doplňky MeSH
• reakční čas MeSH
• sportovní výkon * fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH