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Arterial hypertension is a major cause of mortality and morbidity worldwide. Medical therapy is the most common treatment. However, in some cases there is a persistent high blood pressure despite medical therapy. These patients with medication refractory arterial hypertension can be treated by renal denervation. Until now an endovascular approach has been used. There are however limitations in eligibility based on vascular or anatomical anomalies. For these patients, as well as other patients eligible for renal denervation, robot-assisted renal denervation has the potential to become a surgical treatment option based on our findings.
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BACKGROUND: Tuberculosis (TB) poses a major public health challenge, particularly in children. A substantial proportion of children with TB disease remain undetected and unconfirmed. Therefore, there is an urgent need for a highly sensitive point-of-care test. This study aims to assess the performance of serological assays based on various antigen targets and antibody properties in distinguishing children (0-18 years) with TB disease (1) from healthy TB-exposed children, (2) children with non-TB lower respiratory tract infections, and (3) from children with TB infection. METHODS: The study will use biobanked plasma samples collected from three prospective multicentric diagnostic observational studies: the Childhood TB in Switzerland (CITRUS) study, the Pediatric TB Research Network in Spain (pTBred), and the Procalcitonin guidance to reduce antibiotic treatment of lower respiratory tract infections in children and adolescents (ProPAED) study. Included are children diagnosed with TB disease or infection, healthy TB-exposed children, and sick children with non-TB lower respiratory tract infection. Serological multiplex assays will be performed to identify M. tuberculosis antigen-specific antibody features, including isotypes, subclasses, Fc receptor (FcR) binding, and IgG glycosylation. DISCUSSION: The findings from this study will help to design serological assays for diagnosing TB disease in children. Importantly, those assays could easily be developed as low-cost point-of-care tests, thereby offering a potential solution for resource-constrained settings. GOV IDENTIFIER: NCT03044509.
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Testes Sorológicos , Tuberculose , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Testes Imediatos , Estudos Prospectivos , Testes Sorológicos/métodos , Espanha , Suíça , Tuberculose/diagnóstico , Tuberculose/sangueRESUMO
The temporal resolution of ultrafast electron diffraction at weakly relativistic beam energies (â²100 keV) suffers from space-charge induced electron pulse broadening. We describe the implementation of a radio frequency (RF) cavity operating in the continuous wave regime to compress high repetition rate electron bunches from a 40.4 kV DC photoinjector for ultrafast electron diffraction applications. Active stabilization of the RF amplitude and phase through a feedback loop based on the demodulated in-phase and quadrature components of the RF signal is demonstrated. This scheme yields 144 ± 19 fs RMS temporal resolution in pump-probe studies.
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Ligand activation of the aryl hydrocarbon receptor (AHR) accelerates keratinocyte differentiation and the formation of the epidermal permeability barrier. Several classes of lipids, including ceramides, are critical to the epidermal permeability barrier. In normal human epidermal keratinocytes, the AHR ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin, increased RNA levels of ceramide metabolism and transport genes: uridine diphosphate glucose ceramide glucosyltransferase (UGCG), ABCA12, GBA1, and SMPD1. Levels of abundant skin ceramides were also increased by 2,3,7,8-tetrachlorodibenzo-p-dioxin. These included the metabolites synthesized by UGCG, glucosylceramides, and acyl glucosylceramides. Chromatin immunoprecipitation-sequence analysis and luciferase reporter assays identified UGCG as a direct AHR target. The AHR antagonist, GNF351, inhibited the 2,3,7,8-tetrachlorodibenzo-p-dioxin-mediated RNA and transcriptional increases. Tapinarof, an AHR ligand approved for the treatment of psoriasis, increased UGCG RNA, protein, and its lipid metabolites hexosylceramides as well as increased the RNA expression of ABCA12, GBA1, and SMPD1. In Ahr-null mice, Ugcg RNA and hexosylceramides were lower than those in the wild type. These results indicate that the AHR regulates the expression of UGCG, a ceramide-metabolizing enzyme required for ceramide trafficking, keratinocyte differentiation, and epidermal permeability barrier formation.
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Glucosilceramidas , Dibenzodioxinas Policloradas , Animais , Camundongos , Humanos , Glucosilceramidas/metabolismo , Uridina Difosfato Glucose , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Ligantes , RNARESUMO
The present article entails the emergence of diverse crystal polymorphs following thermal quenching into various coexistence regions of binary azobenzene chromophore (ACh)/diacrylate (DA) solution and of azobenzene/nematic liquid crystal (E7) mixture. Development of various crystal topologies encompassing rhomboidal and hexagonal shapes can be witnessed in a manner dependent on thermal quenched depths into the crystal + liquid coexistence region of ACh/DA system. Upon spraying with compressed carbon dioxide (CO2 ) fluid, the local temperature gradient is generated resulting in spherulitic morphology showing discrete lamellae undergoing twisting locally in some regions and branched dendrites or seaweeds in another. When ACh/E7 blend is sprayed using compressed CO2 fluid, hierarchical organization of various discrete faceted single crystals including needle, rectangular, rhombus, and truncated hexagonal crystals radiating from the spherulite core can be discerned in a brighter region (off cross-polarization) polarized optical microscopy (POM) and nematic disclination in a darker cross-polarized region. Of particular interest is that the observed faceted single-crystal polymorphs in ACh/E7 may be contrasted to the lamellar twisting and branching observed in the ACh/DA system and plausible mechanisms of polymer spherulitic growth are discussed.
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Compostos Azo , Dióxido de Carbono , Cristalização , Compostos Azo/química , Polímeros/químicaRESUMO
Cytochrome P4501B1 (CYP1B1) is elevated in breast cancer. Studies indicate a relationship between CYP1B1 and aggressive cancer phenotypes. Here, we report on in vitro studies in triple-negative breast cancer cell lines, where knockdown (KD) of CYP1B1 was used to determine the influence of its expression on invasive cell phenotypes. CYP1B1 KD in MDA-MB-231 cells resulted in the loss of mesenchymal morphology, altered expression of epithelial-mesenchymal genes, and increased claudin (CLDN) RNA and protein. CYP1B1 KD cells had increased cell-to-cell contact and paracellular barrier function, a reduced rate of cell proliferation, abrogation of migratory and invasive activity, and diminished spheroid formation. Analysis of clinical breast cancer tumor samples revealed an association between tumors exhibiting higher CYP1B1 RNA levels and diminished overall and disease-free survival. Tumor expression of CYP1B1 was inversely associated with CLDN7 expression, and CYP1B1HI/CLDN7LOW identified patients with lower median survival. Cells with CYP1B1 KD had an enhanced chemosensitivity to paclitaxel, 5-fluorouracil, and cisplatin. Our findings that CYP1B1 KD can increase chemosensitivity points to therapeutic targeting of this enzyme. CYP1B1 inhibitors in combination with chemotherapeutic drugs may provide a novel targeted and effective approach to adjuvant or neoadjuvant therapy against certain forms of highly metastatic breast cancer.
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Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Claudinas/genética , Citocromo P-450 CYP1B1/genética , Feminino , Humanos , Fenótipo , RNA , Neoplasias de Mama Triplo Negativas/patologiaAssuntos
Hipernatremia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Fatores de RiscoRESUMO
To determine the cutaneous effects of in utero and lactational exposure to the AHR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), pregnant C57BL/6J mice were exposed by gavage to a vehicle or 5 µg TCDD/kg body weight at embryonic day 12 and epidermal barrier formation and function were studied in their offspring from postnatal day 1 (P1) through adulthood. TCDD-exposed pups were born with acanthosis. This effect was AHR-dependent and subsided by P6 with no evidence of subsequent inflammatory dermatitis. The challenge of adult mice with MC903 showed similar inflammatory responses in control and treated animals, indicating no long-term immunosuppression to this chemical. Chloracne-like sebaceous gland hypoplasia and cyst formation were observed in TCDD-exposed P21 mice, with concomitant microbiome dysbiosis. These effects were reversed by P35. CYP1A1 and CYP1B1 expression in the skin was increased in the exposed mice until P21, then declined. Both CYP proteins co-localized with LRIG1-expressing progenitor cells at the infundibulum. CYP1B1 protein also co-localized with a second stem cell niche in the isthmus. These results indicate that this exposure to TCDD causes a chloracne-like effect without inflammation. Transient activation of the AhR, due to the shorter half-life of TCDD in mice, likely contributes to the reversibility of these effects.
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The epidermis forms a barrier that defends the body from desiccation and entry of harmful substances, while also sensing and integrating environmental signals. The tightly orchestrated cellular changes needed for the formation and maintenance of this epidermal barrier occur in the context of the skin microbiome. Using germ-free mice, we demonstrate the microbiota is necessary for proper differentiation and repair of the epidermal barrier. These effects are mediated by microbiota signaling through the aryl hydrocarbon receptor (AHR) in keratinocytes, a xenobiotic receptor also implicated in epidermal differentiation. Mice lacking keratinocyte AHR are more susceptible to barrier damage and infection, during steady-state and epicutaneous sensitization. Colonization with a defined consortium of human skin isolates restored barrier competence in an AHR-dependent manner. We reveal a fundamental mechanism whereby the microbiota regulates skin barrier formation and repair, which has far-reaching implications for the numerous skin disorders characterized by epidermal barrier dysfunction.
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Microbiota/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Pele/microbiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Diferenciação Celular , Linhagem Celular , Células Epidérmicas/metabolismo , Células Epidérmicas/patologia , Epiderme/metabolismo , Feminino , Humanos , Queratinócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pele/patologia , Dermatopatias/microbiologiaAssuntos
Anti-Infecciosos , Estilbenos , Humanos , Receptores de Hidrocarboneto Arílico , ResorcinóisRESUMO
Unplanned hospital readmissions are a burden to patients and increase healthcare costs. A wide variety of machine learning (ML) models have been suggested to predict unplanned hospital readmissions. These ML models were often specifically trained on patient populations with certain diseases. However, it is unclear whether these specialized ML models-trained on patient subpopulations with certain diseases or defined by other clinical characteristics-are more accurate than a general ML model trained on an unrestricted hospital cohort. In this study based on an electronic health record cohort of consecutive inpatient cases of a single tertiary care center, we demonstrate that accurate prediction of hospital readmissions may be obtained by general, disease-independent, ML models. This general approach may substantially decrease the cost of development and deployment of respective ML models in daily clinical routine, as all predictions are obtained by the use of a single model.
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Hospitalização , Aprendizado de Máquina , Modelos Estatísticos , Readmissão do Paciente , Área Sob a Curva , Doenças Cardiovasculares , Doença Crônica , Estudos de Coortes , Conjuntos de Dados como Assunto , Registros Eletrônicos de Saúde , Feminino , Humanos , Pneumopatias , Masculino , Neoplasias , Prognóstico , Centros de Atenção Terciária , Resultado do TratamentoRESUMO
Activation of the aryl hydrocarbon receptor (AHR) in normal human epidermal keratinocytes (NHEKs) accelerates keratinocyte terminal differentiation through metabolic reprogramming and reactive oxygen species (ROS) production. Of the three NOS isoforms, NOS3 is significantly increased at both the RNA and protein levels by exposure to the very potent and selective ligand of the AHR, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Inhibition of NOS with the chemical N-nitro-l-arginine methyl ester (l-NAME) reversed TCDD-induced cornified envelope formation, an endpoint of terminal differentiation, as well as the expression of filaggrin (FLG), a marker of differentiation. Conversely, exposure to the NO-donor, S-nitroso-N-acetyl-DL-penicillamine (SNAP), increased the number of cornified envelopes above control levels and augmented the levels of cornified envelopes formed in response to TCDD treatment and increased the expression of FLG. This indicates that nitric oxide signaling can increase keratinocyte differentiation and that it is involved in the AHR-mediated acceleration of differentiation. As the nitrosylation of cysteines is a mechanism by which NO affects the structure and functions of proteins, the S-nitrosylation biotin switch technique was used to measure protein S-nitrosylation. Activation of the AHR increased the S-nitrosylation of two detected proteins of about 72 and 20 kD in size. These results provide new insights into the role of NO and protein nitrosylation in the process of epithelial cell differentiation, suggesting a role of NOS in metabolic reprogramming and the regulation of epithelial cell fate.
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Diferenciação Celular , Queratinócitos/citologia , Queratinócitos/metabolismo , Óxido Nítrico/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Epiderme/metabolismo , Proteínas Filagrinas , Humanos , Ligantes , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Nitrosação , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
INTRODUCTION: Emotions are theorized to contain the components of affect and action readiness. Affect guides behavior by causing an approach or withdrawal orientation. Action readiness is the individual's degree of willingness to interact with the environment. Emotions contribute to changes in behavior and physiological responses. AIM: The present study applied these notions to sexuality and examined the associations between affect, action readiness, and sexual functioning. METHODS: Participants were male patients with urologic condition (N = 70) with and without sexual problems. MAIN OUTCOME MEASURE: Affect and action readiness were jointly assessed using the latent factor of affective polarity of the Positive and Negative Affect Schedule. Trait affective polarity was assessed questioning generally experienced feelings. State affective polarity was assessed after exposure to an erotic stimulus and questioning momentaneously experienced feelings. Sexual functioning was assessed using the International Index of Erectile Functioning questionnaire. RESULTS: A significant increase of approach-oriented action readiness was found after erotic stimulation, relative to trait levels. In addition, significant associations were found between state approach-oriented action readiness and various aspects of sexual functioning. Interventions based on principles of positive psychology might be developed to reinforce action readiness in men with erectile dysfunction. The strength of the current research concerns the introduction of action readiness as a potential psychological factor implied in sexual functioning. Limitations pertain to the use of the algorithm used to calculate state approach-oriented action readiness and the use of the current sample of patients with urological conditions, limiting generalizability of findings. CONCLUSION: Action readiness was found to correlate positively with all aspects of sexual functioning. Further research into the role of action readiness in sexuality is recommended. Henckens MJMJ, de Vries P, Janssen E, et al. Associations of Affect, Action Readiness, and Sexual Functioning. Sex Med 2020;8:691-698.
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Rationale: Tuberculosis diagnosis in children remains challenging. Microbiological confirmation of tuberculosis disease is often lacking, and standard immunodiagnostic including the tuberculin skin test and interferon-γ release assay for tuberculosis infection has limited sensitivity. Recent research suggests that inclusion of novel Mycobacterium tuberculosis antigens has the potential to improve standard immunodiagnostic tests for tuberculosis. Objective: To identify optimal antigen-cytokine combinations using novel Mycobacterium tuberculosis antigens and cytokine read-outs by machine learning algorithms to improve immunodiagnostic assays for tuberculosis. Methods: A total of 80 children undergoing investigation of tuberculosis were included (15 confirmed tuberculosis disease, five unconfirmed tuberculosis disease, 28 tuberculosis infection and 32 unlikely tuberculosis). Whole blood was stimulated with 10 novel Mycobacterium tuberculosis antigens and a fusion protein of early secretory antigenic target (ESAT)-6 and culture filtrate protein (CFP) 10. Cytokines were measured using xMAP multiplex assays. Machine learning algorithms defined a discriminative classifier with performance measured using area under the receiver operating characteristics. Measurements and main results: We found the following four antigen-cytokine pairs had a higher weight in the discriminative classifier compared to the standard ESAT-6/CFP-10-induced interferon-γ: Rv2346/47c- and Rv3614/15c-induced interferon-gamma inducible protein-10; Rv2031c-induced granulocyte-macrophage colony-stimulating factor and ESAT-6/CFP-10-induced tumor necrosis factor-α. A combination of the 10 best antigen-cytokine pairs resulted in area under the curve of 0.92 ± 0.04. Conclusion: We exploited the use of machine learning algorithms as a key tool to evaluate large immunological datasets. This identified several antigen-cytokine pairs with the potential to improve immunodiagnostic tests for tuberculosis in children.
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Mycobacterium tuberculosis , Tuberculose , Algoritmos , Antígenos de Bactérias , Proteínas de Bactérias , Criança , Humanos , Imunidade , Aprendizado de Máquina , Tuberculose/diagnósticoRESUMO
Activation of the transcription factor, AHR, in normal human epidermal keratinocytes increased AHR binding in the gene regions of the glucose transporter, SLC2A1, and the glycolytic enzyme, ENO1. This increased chromatin binding corresponded with AHR-dependent decreases in levels of SLC2A1 and ENO1 mRNA, protein, and activities. Studies of the ENO1 promoter showed activation of the AHR decreases the transcription of ENO1. Glycolysis was lowered by activation of the AHR as measured by decreases in glucose uptake and the production of pyruvate and lactate. Levels of ATP were also decreased. Downregulation of glucose metabolism, either by activation of the AHR, inhibition of glycolysis, inhibition of glucose transport, or inhibition of enolase, increased SIRT1 protein levels in normal human epidermal keratinocytes and the immortalized keratinocyte cell line, N/TERT-1. This increase in SIRT1 was abrogated by the addition of exogenous pyruvate. Moreover, keratinocyte differentiation in response to downregulation of glycolysis, either by activation of the AHR, inhibition of glucose transport, or inhibition of enolase, was dependent on SIRT1. These results indicate that regulation of glycolysis controls keratinocyte differentiation, and that activation of the AHR, by lowering the expression of SLC2A1 and ENO1, can determine this fate.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Epiderme/metabolismo , Regulação da Expressão Gênica , Queratinócitos/metabolismo , RNA/genética , Receptores de Hidrocarboneto Arílico/genética , Sirtuína 1/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Células Cultivadas , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Glucose/metabolismo , Transportador de Glucose Tipo 1/biossíntese , Transportador de Glucose Tipo 1/genética , Glicólise/fisiologia , Humanos , Queratinócitos/citologia , Fosfopiruvato Hidratase/biossíntese , Fosfopiruvato Hidratase/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Sirtuína 1/biossíntese , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genéticaRESUMO
BACKGROUND: Cigarette smoke contains compounds similar to coal tar, an ancient remedy of eczema. Some studies have reported protective effects of maternal gestational smoking on offspring eczema; however, others have shown no or increased risks. Similarly, studies linking breastfeeding duration and eczema have demonstrated contradictory findings. No study has yet investigated combined effects of these two factors on eczema. OBJECTIVE: Since tobacco compounds can pass to offspring via breast milk, we investigated their combined effects on eczema development from childhood to adolescence. METHODS: We obtained information regarding gestational smoking, exclusive breastfeeding duration, and eczema at ages 1-or-2, 4, 10, and 18 years from the Isle of Wight (IOW) birth cohort, UK. Using generalized estimating equations, we assessed the interaction of gestational smoking and residual exclusive breastfeeding duration (Resid-BF-duration, obtained by regressing the latter on maternal smoking) on eczema over time adjusting for confounders. For the three transition periods of 1-or-2 to 4 years, 4-10, and 10-18 years, we estimated risks of persistent, incident, and remitting eczema associated with the interaction using repeated measurements. RESULTS: If the mother smoked during gestation, longer Resid-BF-duration was associated with a lower risk of eczema, compared to if she did not smoke. The risk ratios (95% CI) if the mother smoked during gestation and exclusively breastfed for at least 3, 9, 15, 21 weeks are 0.7 (0.6, 1.7), 0.6 (0. 4, 0.9), 0.5 (0.3, 0.8), and 0.4 (0.2, 0. 8), respectively. Additionally, in all three transition periods, the risk of persistent eczema was lower with longer Resid-BF-duration if the mother smoked during gestation. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest a protective effect of gestational smoking combined with longer duration of exclusive breastfeeding on early-onset persistent eczema. Future studies should examine underlying biological mechanisms. Prolonged breastfeeding should be encouraged even if the mother smoked during gestation.
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Aleitamento Materno , Eczema/epidemiologia , Eczema/etiologia , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Fumar , Adolescente , Fatores Etários , Biomarcadores , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Masculino , Gravidez , Vigilância em Saúde Pública , Medição de Risco , Fumar/efeitos adversosRESUMO
A novel pathway of vitamin D activation by CYP11A has previously been elucidated. To define the mechanism of action of its major dihydroxy-products, we tested the divergence and overlap between the gene expression profiles of human epidermal keratinocytes treated with either CYP11A1-derived 20,23(OH)2D3 or classical 1,25(OH)2D3. Both secosteroids have significant chemical similarity with the only differences being the positions of the hydroxyl groups. mRNA was isolated and examined by microarray analysis using Illumina's HumanWG-6 chip/arrays and subsequent bioinformatics analyses. Marked differences in the up- and downregulated genes were observed between 1,25(OH)2D3- and 20,23(OH)2D3-treated cells. Hierarchical clustering identified both distinct, opposite and common (overlapping) gene expression patterns. CYP24A1 was a common gene strongly activated by both compounds, a finding confirmed by qPCR. Ingenuity pathway analysis identified VDR/RXR signaling as the top canonical pathway induced by 1,25(OH)2D3. In contrast, the top canonical pathway induced by 20,23(OH)2D3 was AhR, with VDR/RXR being the second nuclear receptor signaling pathway identified. QPCR analyses validated the former finding by revealing that 20,23(OH)2D3 stimulated CYP1A1 and CYP1B1 gene expression, effects located downstream of AhR. Similar stimulation was observed with 20(OH)D3, the precursor to 20,23(OH)2D3, as well as with its downstream metabolite, 17,20,23(OH)3D3. Using a Human AhR Reporter Assay System we showed marked activation of AhR activity by 20,23(OH)2D3, with weaker stimulation by 20(OH)D3. Finally, molecular modeling using an AhR LBD model predicted vitamin D3 hydroxyderivatives to be good ligands for this receptor. Thus, our microarray, qPCR, functional studies and molecular modeling indicate that AhR is the major receptor target for 20,23(OH)2D3, opening an exciting area of investigation on the interaction of different vitamin D3-hydroxyderivatives with AhR and the subsequent downstream activation of signal transduction pathways in a cell-type-dependent manner.
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Calcitriol/farmacologia , Di-Hidroxicolecalciferóis/farmacologia , Queratinócitos/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Sítios de Ligação , Células Cultivadas , Humanos , Queratinócitos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Ligação Proteica , Receptores de Hidrocarboneto Arílico/químicaRESUMO
Diurnal oscillation of intracellular redox potential is known to couple metabolism with the circadian clock, yet the responsible mechanisms are not well understood. We show here that chemical activation of NRF2 modifies circadian gene expression and rhythmicity, with phenotypes similar to genetic NRF2 activation. Loss of Nrf2 function in mouse fibroblasts, hepatocytes and liver also altered circadian rhythms, suggesting that NRF2 stoichiometry and/or timing of expression are important to timekeeping in some cells. Consistent with this concept, activation of NRF2 at a circadian time corresponding to the peak generation of endogenous oxidative signals resulted in NRF2-dependent reinforcement of circadian amplitude. In hepatocytes, activated NRF2 bound specific enhancer regions of the core clock repressor gene Cry2, increased Cry2 expression and repressed CLOCK/BMAL1-regulated E-box transcription. Together these data indicate that NRF2 and clock comprise an interlocking loop that integrates cellular redox signals into tissue-specific circadian timekeeping.
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Proteínas CLOCK/metabolismo , Relógios Circadianos , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular , Regulação da Expressão Gênica , Camundongos , OxirreduçãoRESUMO
The Kelch-like erythroid-associated protein 1 (Keap1)-NF-E2-related factor 2 (Nrf2) signaling pathway is the subject of several clinical trials evaluating the effects of Nrf2 activation on the prevention of cancer and diabetes and the treatment of chronic kidney disease and multiple sclerosis. 3H-1,2-dithiole-3-thione (D3T) and 1-[2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im) are representative members of two distinct series of Nrf2 chemical activators. Previous reports have described activator-specific effects on Nrf2-dependent gene regulation and physiologic outcomes. Here we used a robust chemical genomics approach to characterize expression profiles between D3T and CDDO-Im in livers from wild-type and Nrf2-null mice. At equally efficacious doses in wild-type mice, 406 genes show common RNA responses to both treatments. These genes enriched the Nrf2-regulated pathways of antioxidant defense and xenobiotic metabolism. In addition, 197 and 745 genes were regulated uniquely in response to either D3T or CDDO-Im, respectively. Functional analysis of the D3T-regulated set showed a significant enrichment of Nrf2-regulated enzymes involved in cholesterol biosynthesis. This result was supported by Nrf2-dependent increases in lanosterol synthase and CYP51 protein expression. CDDO-Im had no effect on cholesterol biosynthesis regardless of the dose tested. However, unlike D3T, CDDO-Im resulted in Nrf2-dependent elevation of peroxisome proliferator α and Kruppel-like factor 13, as well as the coactivator peroxisome proliferator γ coactivator 1ß, together indicating regulation of ß-oxidation and lipid metabolic pathways. These findings provide novel insights into the pharmacodynamic action of these two activators of Keap1-Nrf2 signaling. Although both compounds modify Keap1 to affect canonical cytoprotective gene expression, additional unique sets of Nrf2-dependent genes were regulated by each agent with enrichment of selective metabolic pathways.