Nejvíce citovaný článek - PubMed ID 16841097
The literature documenting the value of drug-like molecules found in natural products is vast. Although many dietary and herbal remedies have been found to be effective for treating intestinal inflammation, the identification of their active components has lagged behind. In this study, we find that a major ginger component, furanodienone (FDN), is a selective pregnane X receptor (PXR) ligand with agonistic transcriptional outcomes. We show that FDN binds within a sub-pocket of the PXR ligand binding domain (LBD), with subsequent alterations in LBD structure. Using male mice, we show that orally provided FDN has potent PXR-dependant anti-inflammatory outcomes that are colon-specific. Increased affinity and target gene activation in the presence of synergistically acting agonists indicates further opportunities for augmenting FDN activity, efficacy and safety. Collectively, these results support the translational potential of FDN as a therapeutic agent for the treatment and prevention of colonic diseases.
- MeSH
- antiflogistika farmakologie chemie MeSH
- furany farmakologie MeSH
- kolitida farmakoterapie chemicky indukované metabolismus patologie MeSH
- kolon účinky léků patologie metabolismus MeSH
- lidé MeSH
- ligandy MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- pregnanový X receptor * metabolismus genetika MeSH
- zánět farmakoterapie metabolismus MeSH
- zázvor lékařský * chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- antiflogistika MeSH
- furany MeSH
- ligandy MeSH
- pregnanový X receptor * MeSH
National screening programs use dried blood specimens to detect metabolic disorders or aberrant protein functions that are not clinically evident in the neonatal period. Similarly, gut microbiota metabolites and immunological acute-phase proteins may reveal latent immune aberrations. Microbial metabolites interact with xenobiotic receptors (i.e., aryl hydrocarbon and pregnane-X) to maintain gastrointestinal tissue health, supported by acute-phase proteins, functioning as sensors of microbial immunomodulation and homeostasis. The delivery (vaginal or cesarean section) shapes the microbial colonization, which substantially modulates both the immune system's response and mucosal homeostasis. This study profiled microbial metabolites of the kynurenine and tryptophan pathway and acute-phase proteins in 134 neonatal dried blood specimens. We newly established neonatal blood levels of microbial xenobiotic receptors ligands (i.e., indole-3-aldehyde, indole-3-butyric acid, and indole-3-acetamide) on the second day of life. Furthermore, we observed diverse microbial metabolic profiles in neonates born vaginally and via cesarean section, potentially due to microbial immunomodulatory influence. In summary, these findings suggest the supportive role of human gut microbiota in developing and maintaining immune system homeostasis.
- Klíčová slova
- acute-phase proteins, dried blood specimens, human gut microbiota, immunomodulation, tryptophan and kynurenine metabolism,
- Publikační typ
- časopisecké články MeSH
The pregnane X receptor (PXR, encoded by the NR1I2 gene) is a ligand-regulated transcription factor originally described as a master regulator of xenobiotic detoxification. Later, however, PXR was also shown to interact with endogenous metabolism and to be further associated with various pathological states. This review focuses predominantly on such aspects, currently less covered in literature, as the control of PXR expression per se in the context of inter-individual differences in drug metabolism. There is growing evidence that non-coding RNAs post-transcriptionally regulate PXR. Effects on PXR have especially been reported for microRNAs (miRNAs), which include miR-148a, miR-18a-5p, miR-140-3p, miR-30c-1-3p and miR-877-5p. Likewise, miRNAs control the expression of both transcription factors involved in PXR expression and regulators of PXR function. The impact of NR1I2 genetic polymorphisms on miRNA-mediated PXR regulation is also discussed. As revealed recently, long non-coding RNAs (lncRNAs) appear to interfere with PXR expression. Reciprocally, PXR activation regulates non-coding RNA expression, thus comprising another level of PXR action in addition to the direct transactivation of protein-coding genes. PXR expression is further controlled by several transcription factors (cross-regulation) giving rise to different PXR transcript variants. Controversies remain regarding the suggested role of feedback regulation (auto-regulation) of PXR expression. In this review, we comprehensively summarize the miRNA-mediated, lncRNA-mediated and transcriptional regulation of PXR expression, and we propose that deciphering the precise mechanisms of PXR expression may bridge our knowledge gap in inter-individual differences in drug metabolism and toxicity.
- Klíčová slova
- CYP3A4, Gene expression, Non-coding RNA, Post-transcriptional regulation, Pregnane X receptor, microRNA,
- MeSH
- biologická variabilita populace * MeSH
- biotransformace MeSH
- farmakogenetika MeSH
- farmakogenomické varianty * MeSH
- fenotyp MeSH
- genetická transkripce * MeSH
- genotyp MeSH
- lidé MeSH
- mikro RNA genetika metabolismus MeSH
- posttranskripční úpravy RNA * MeSH
- pregnanový X receptor genetika metabolismus MeSH
- RNA dlouhá nekódující genetika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- mikro RNA MeSH
- NR1I2 protein, human MeSH Prohlížeč
- pregnanový X receptor MeSH
- RNA dlouhá nekódující MeSH
Pregnane X Receptor (PXR) is a ligand-activated transcription factor which binds many structurally different molecules. The receptor is able to regulate the expression of a wide array of genes and is involved in cancer and different key physiological processes such as the metabolism of drugs/xenobiotics and endogenous compounds including lipids and carbohydrates, and inflammation. Algae, sponges, sea squirts, and other marine organisms are some of the species from which structurally new molecules have been isolated that have been subsequently identified in recent decades as ligands for PXR. The therapeutic potential of these natural compounds is promising in different areas and has recently resulted in the registration of trabectedin by the FDA as a novel antineoplastic drug. Apart from being potentially novel drugs, these compounds can also serve as models for the development of new molecules with improved activity. The aim of this review is to succinctly summarize the currently known natural molecules isolated from marine organisms with a proven ability to interact with PXR.
- Klíčová slova
- CYP450, PXR, cancer, gene regulation, inflammation, marine origin, natural compound,
- MeSH
- biologické přípravky chemie izolace a purifikace farmakologie MeSH
- lidé MeSH
- ligandy MeSH
- molekulární struktura MeSH
- Porifera chemie MeSH
- pregnanový X receptor metabolismus MeSH
- regulace genové exprese účinky léků MeSH
- Urochordata chemie MeSH
- vodní organismy chemie MeSH
- vyvíjení léků * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- biologické přípravky MeSH
- ligandy MeSH
- pregnanový X receptor MeSH
The pregnane X receptor (PXR) is a drug/xenobiotic-activated transcription factor of crucial importance for major cytochrome P450 xenobiotic-metabolizing enzymes (CYP) expression and regulation in the liver and the intestine. One of the major target genes regulated by PXR is the cytochrome P450 enzyme (CYP3A4), which is the most important human drug-metabolizing enzyme. In addition, PXR is supposed to be involved both in basal and/or inducible expression of many other CYPs, such as CYP2B6, CYP2C8, 2C9 and 2C19, CYP3A5, CYP3A7, and CYP2A6. Interestingly, the dynamics of PXR-mediated target genes regulation has not been systematically studied and we have only a few mechanistic mathematical and biologically based models describing gene expression dynamics after PXR activation in cellular models. Furthermore, few indirect mathematical PKPD models for prediction of CYP3A metabolic activity in vivo have been built based on compartmental models with respect to drug⁻drug interactions or hormonal crosstalk. Importantly, several negative feedback loops have been described in PXR regulation. Although current mathematical models propose these adaptive mechanisms, a comprehensive mathematical model based on sufficient experimental data is still missing. In the current review, we summarize and compare these models and address some issues that should be considered for the improvement of PXR-mediated gene regulation modelling as well as for our better understanding of the quantitative and spatial dynamics of CYPs expression.
- Klíčová slova
- Pregnane X receptor, gene regulation, mathematical models, simulation,
- MeSH
- genové regulační sítě * MeSH
- lidé MeSH
- pregnanový X receptor MeSH
- steroidní receptory genetika metabolismus MeSH
- systém (enzymů) cytochromů P-450 genetika metabolismus MeSH
- teoretické modely * MeSH
- zpětná vazba fyziologická MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- pregnanový X receptor MeSH
- steroidní receptory MeSH
- systém (enzymů) cytochromů P-450 MeSH
Pregnane X receptor is a ligand-activated nuclear receptor (NR) that mainly controls inducible expression of xenobiotics handling genes including biotransformation enzymes and drug transporters. Nowadays it is clear that PXR is also involved in regulation of intermediate metabolism through trans-activation and trans-repression of genes controlling glucose, lipid, cholesterol, bile acid, and bilirubin homeostasis. In these processes PXR cross-talks with other NRs. Accumulating evidence suggests that the cross-talk is often mediated by competing for common coactivators or by disruption of coactivation and activity of other transcription factors by the ligand-activated PXR. In this respect mainly PXR-CAR and PXR-HNF4α interference have been reported and several cytochrome P450 enzymes (such as CYP7A1 and CYP8B1), phase II enzymes (SULT1E1, Gsta2, Ugt1a1), drug and endobiotic transporters (OCT1, Mrp2, Mrp3, Oatp1a, and Oatp4) as well as intermediate metabolism enzymes (PEPCK1 and G6Pase) have been shown as down-regulated genes after PXR activation. In this review, I summarize our current knowledge of PXR-mediated repression and coactivation interference in PXR-controlled gene expression regulation.
- Klíčová slova
- PXR, cross-talk, gene regulation, metabolism, nuclear receptor,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Pregnane X receptor (PXR) is a member of the nuclear receptor (NR) superfamily of ligand-activated transcription factors and is activated by a huge variety of endobiotics and xenobiotics, including many clinical drugs. PXR plays key roles not only as a xenosensor in the regulation of both major phase I and II drug metabolism and transporters but also as a physiological sensor in the modulation of bile acid and cholesterol metabolism, glucose and lipid metabolism, and bone and endocrine homeostasis. Post-translational modifications such as phosphorylation have been shown to modulate the activity of many NRs, including PXR, and constitute an important mechanism for crosstalk between signaling pathways and regulation of genes involved in both xenobiotic and endobiotic metabolism. In addition, microRNAs have recently been shown to constitute another level of PXR activity regulation. The objective of this review is to comprehensively summarize current understanding of post-transcriptional and post-translational modifications of PXR in regulation of xenobiotic-metabolizing cytochrome P450 (CYP) genes, mainly in hepatic tissue. We also discuss the importance of PXR in crosstalk with cell signaling pathways, which at the level of transcription modify expression of genes associated with some physiological and pathological stages in the organs. Finally, we indicate that these PXR modifications may have important impacts on CYP-mediated biotransformation of some clinically used drugs.
- MeSH
- biotransformace MeSH
- enzymová indukce účinky léků MeSH
- interakční proteinové domény a motivy MeSH
- játra účinky léků enzymologie metabolismus MeSH
- lidé MeSH
- messenger RNA metabolismus MeSH
- posttranskripční úpravy RNA * účinky léků MeSH
- posttranslační úpravy proteinů * účinky léků MeSH
- pregnanový X receptor MeSH
- steroidní receptory chemie genetika metabolismus MeSH
- systém (enzymů) cytochromů P-450 genetika metabolismus MeSH
- xenobiotika metabolismus farmakokinetika toxicita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- messenger RNA MeSH
- pregnanový X receptor MeSH
- steroidní receptory MeSH
- systém (enzymů) cytochromů P-450 MeSH
- xenobiotika MeSH