Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.324
Filtrar
1.
Phys Chem Chem Phys ; 23(36): 20230-20246, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34474468

RESUMO

Research on action selectivity between CYP1A1 and CYP1B1 is particularly valuable for cancer chemoprevention and chemotherapy. However, they share a very close similarity in their ligand-binding pockets that α-naphthoflavone (ANF) is the co-crystal ligand for both isoforms, which poses a major challenge in revealing their selectivity mechanism. Therefore, three selective CYP1B1 inhibitors derived from ANF were selected to illustrate the structural basis for the selectivity between the two isoforms via a comprehensive computational strategy. It was found that the sustainability of the π-π stacking interactions with the phenylalanine residues of the two isoforms, namely, Phe123, Phe224, and Phe258 for CYP1A1, and Phe134, Phe231, and Phe268 for CYP1B1, played a crucial role in determining the selectivity of ligands with a classic aromatic conjugation system like ANF and its derivatives for CYP1B1 versus CYP1A1. Of note, the structural flexibility of the corresponding protein domains mainly orchestrated the sustainability of the corresponding π-π stacking interactions, thereby determining the binding selectivity. Therefore, the structure modification of naphthoflavone lead compounds into preferable binding configurations to satisfy the π-π stacking interactions of the key phenylalanine residues within CYP1B1 would be an inspiring strategy devised to improve the inhibitory selectivity towards CYP1B1. Collectively, this study revealed valuable insight into understanding the selective mechanism between CYP1A1 and CYP1B1 from the perspective of structural flexibility, which sheds light on the future rational design of CYP1B1 selective inhibitors.


Assuntos
Benzoflavonas/farmacologia , Citocromo P-450 CYP1A1/antagonistas & inibidores , Citocromo P-450 CYP1B1/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Benzoflavonas/química , Citocromo P-450 CYP1A1/química , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/química , Citocromo P-450 CYP1B1/metabolismo , Inibidores Enzimáticos/química , Humanos , Simulação de Dinâmica Molecular , Estrutura Molecular
2.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34360828

RESUMO

The environmental pollutant benzo[a]pyrene (BaP) is a human carcinogen that reacts with DNA after metabolic activation catalysed by cytochromes P450 (CYP) 1A1 and 1B1 together with microsomal epoxide hydrolase. The azo dye Sudan I is a potent inducer of CYP1A1/2. Here, Wistar rats were either treated with single doses of BaP (150 mg/kg bw) or Sudan I (50 mg/kg bw) alone or with both compounds in combination to explore BaP-derived DNA adduct formation in vivo. Using 32P-postlabelling, DNA adducts generated by BaP-7,8-dihydrodiol-9,10-epoxide were found in livers of rats treated with BaP alone or co-exposed to Sudan I. During co-exposure to Sudan I prior to BaP treatment, BaP-DNA adduct levels increased 2.1-fold in comparison to BaP treatment alone. Similarly, hepatic microsomes isolated from rats exposed to Sudan I prior to BaP treatment were also the most effective in generating DNA adducts in vitro with the activated metabolites BaP-7,8-dihydrodiol or BaP-9-ol as intermediates. DNA adduct formation correlated with changes in the expression and/or enzyme activities of CYP1A1, 1A2 and 1B1 in hepatic microsomes. Thus, BaP genotoxicity in rats in vivo appears to be related to the enhanced expression and/or activity of hepatic CYP1A1/2 and 1B1 caused by exposure of rats to the studied compounds. Our results indicate that the industrially employed azo dye Sudan I potentiates the genotoxicity of the human carcinogen BaP, and exposure to both substances at the same time seems to be hazardous to humans.


Assuntos
Benzo(a)pireno/toxicidade , Citocromo P-450 CYP1A1/metabolismo , Adutos de DNA/toxicidade , Fígado/efeitos dos fármacos , Microssomos Hepáticos/efeitos dos fármacos , Naftóis/toxicidade , Animais , Carcinógenos Ambientais/toxicidade , Corantes/toxicidade , Masculino , Ratos , Ratos Wistar
3.
Sci Rep ; 11(1): 16629, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404832

RESUMO

Since understanding molecular mechanisms of SARS-CoV-2 infection is extremely important for developing effective therapies against COVID-19, we focused on the internalization mechanism of SARS-CoV-2 via ACE2. Although cigarette smoke is generally believed to be harmful to the pathogenesis of COVID-19, cigarette smoke extract (CSE) treatments were surprisingly found to suppress the expression of ACE2 in HepG2 cells. We thus tried to clarify the mechanism of CSE effects on expression of ACE2 in mammalian cells. Because RNA-seq analysis suggested that suppressive effects on ACE2 might be inversely correlated with induction of the genes regulated by aryl hydrocarbon receptor (AHR), the AHR agonists 6-formylindolo(3,2-b)carbazole (FICZ) and omeprazole (OMP) were tested to assess whether those treatments affected ACE2 expression. Both FICZ and OMP clearly suppressed ACE2 expression in a dose-dependent manner along with inducing CYP1A1. Knock-down experiments indicated a reduction of ACE2 by FICZ treatment in an AHR-dependent manner. Finally, treatments of AHR agonists inhibited SARS-CoV-2 infection into Vero E6 cells as determined with immunoblotting analyses detecting SARS-CoV-2 specific nucleocapsid protein. We here demonstrate that treatment with AHR agonists, including FICZ, and OMP, decreases expression of ACE2 via AHR activation, resulting in suppression of SARS-CoV-2 infection in mammalian cells.


Assuntos
Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , COVID-19/tratamento farmacológico , Carbazóis/farmacologia , Omeprazol/farmacologia , Receptores de Hidrocarboneto Arílico/agonistas , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , COVID-19/virologia , Carbazóis/uso terapêutico , Chlorocebus aethiops , Citocromo P-450 CYP1A1/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Omeprazol/uso terapêutico , RNA-Seq , Receptores de Hidrocarboneto Arílico/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/patogenicidade , Transdução de Sinais/efeitos dos fármacos , Células Vero , Internalização do Vírus/efeitos dos fármacos
4.
Nutrients ; 13(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34371875

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) have been recognized to cause neurobehavioral dysfunctions and disorder of cognition and behavioral patterns in childhood. Momordica charantia L. (MC) has been widely known for its nutraceutical and health-promoting properties. To date, the effect of MC for the prevention and handling of PAHs-induced neurotoxicity has not been reported. In the current study, the neuroprotective effects of MC and its underlying mechanisms were investigated in mouse hippocampal neuronal cell line (HT22); moreover, in silico analysis was performed with the phytochemicals MC to decipher their potential function as neuroprotectants. MC was demonstrated to possess neuroprotective effect by reducing reactive oxygen species' (ROS') production and down-regulating cyclin D1, p53, and p38 mitogen-activated protein kinase (MAPK) protein expressions, resulting in the inhibition of cell apoptosis and the normalization of cell cycle progression. Additionally, 28 phytochemicals of MC and their competence on inhibiting cytochrome P450 (CYP: CYP1A1, CYP1A2, and CYP1B1) functions were resolved. In silico analysis of vitamin E and stigmasterol revealed that their binding to either CYP1A1 or CYP1A2 was more efficient than the binding of each positive control (alizarin or purpurin). Together, MC is potentially an interesting neuroprotectant including vitamin E and stigmasterol as probable active components for the prevention for PAHs-induced neurotoxicity.


Assuntos
Hipocampo/efeitos dos fármacos , Momordica charantia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Estigmasterol/farmacologia , Vitamina E/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Momordica charantia/química , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Estigmasterol/isolamento & purificação , Vitamina E/isolamento & purificação
5.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299011

RESUMO

Osteoporosis is the most common metabolic bone disorder and nitrogen-containing bisphosphonates (BP) are a first line treatment for it. Yet, atypical femoral fractures (AFF), a rare adverse effect, may appear after prolonged BP administration. Given the low incidence of AFF, an underlying genetic cause that increases the susceptibility to these fractures is suspected. Previous studies uncovered rare CYP1A1 mutations in osteoporosis patients who suffered AFF after long-term BP treatment. CYP1A1 is involved in drug metabolism and steroid catabolism, making it an interesting candidate. However, a functional validation for the AFF-associated CYP1A1 mutations was lacking. Here we tested the enzymatic activity of four such CYP1A1 variants, by transfecting them into Saos-2 cells. We also tested the effect of commonly used BPs on the enzymatic activity of the CYP1A1 forms. We demonstrated that the p.Arg98Trp and p.Arg136His CYP1A1 variants have a significant negative effect on enzymatic activity. Moreover, all the BP treatments decreased CYP1A1 activity, although no specific interaction with CYP1A1 variants was found. Our results provide functional support to the hypothesis that an additive effect between CYP1A1 heterozygous mutations p.Arg98Trp and p.Arg136His, other rare mutations and long-term BP exposure might generate susceptibility to AFF.


Assuntos
Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Fraturas do Fêmur/genética , Fraturas do Fêmur/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Citocromo P-450 CYP1A1/química , Difosfonatos/uso terapêutico , Fraturas do Fêmur/enzimologia , Humanos , Incidência , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Filogenia , Alinhamento de Sequência
6.
Int J Mol Sci ; 22(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201250

RESUMO

Breast cancer (BC) is a leading cause of cancer deaths in women in less developed countries and the second leading cause of cancer death in women in the U.S. In this study, we report the inhibition of E2-mediated mammary tumorigenesis by Cuminum cyminum (cumin) administered via the diet as cumin powder, as well as dried ethanolic extract. Groups of female ACI rats were given either an AIN-93M diet or a diet supplemented with cumin powder (5% and 7.5%, w/w) or dried ethanolic cumin extract (1%, w/w), and then challenged with subcutaneous E2 silastic implants (1.2 cm; 9 mg). The first appearance of a palpable mammary tumor was significantly delayed by both the cumin powder and extract. At the end of the study, the tumor incidence was 96% in the control group, whereas only 55% and 45% animals had palpable tumors in the cumin powder and extract groups, respectively. Significant reductions in tumor volume (660 ± 122 vs. 138 ± 49 and 75 ± 46 mm3) and tumor multiplicity (4.21 ± 0.43 vs. 1.16 ± 0.26 and 0.9 ± 0.29 tumors/animal) were also observed by the cumin powder and cumin extract groups, respectively. The cumin powder diet intervention dose- and time-dependently offset E2-related pituitary growth, and reduced the levels of circulating prolactin and the levels of PCNA in the mammary tissues. Mechanistically, the cumin powder diet resulted in a significant reversal of E2-associated modulation in ERα, CYP1A1 and CYP1B1. Further, the cumin powder diet reversed the expression levels of miRNAs (miR-182, miR-375, miR-127 and miR-206) that were highly modulated by E2 treatment. We analyzed the composition of the extract by GC/MS and established cymene and cuminaldehyde as major components, and further detected no signs of gross or systemic toxicity. Thus, cumin bioactives can significantly delay and prevent E2-mediated mammary tumorigenesis in a safe and effective manner, and warrant continued efforts to develop these clinically translatable spice bioactives as chemopreventives and therapeutics against BC.


Assuntos
Cuminum/química , Estradiol/toxicidade , Estrogênios/toxicidade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Mamárias Experimentais/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Feminino , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , MicroRNAs/genética , Ratos , Ratos Endogâmicos ACI
7.
Environ Toxicol Pharmacol ; 87: 103704, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273545

RESUMO

A luciferase reporter gene-based bioassay battery consisting of stress-activated receptors from fish, complemented with traditional fish cell-based bioassays, were used to assess the toxicity of marine sediment samples from the Byfjorden area around the city of Bergen (Norway). The reporter assays covered a wide range of cellular signalling and metabolic pathways, representing different molecular initiating events in the adverse outcome pathway framework. Cytotoxicity, generation of reactive oxygen-species, and induction of 7-ethoxyresorufin-O-deethylase activity were analysed using fish liver and gill cell lines. Chemical analyses of the sediment extracts revealed complex contamination profiles, especially at the innermost stations, which contained a wide array of persistent organic pollutants, polycyclic aromatic hydrocarbons, and metals. Sediment extracts from these sites were more potent in activating the stress-activated receptors than the other extracts, reflecting their toxicant profiles. Importantly, receptor- and cell-based bioassays complemented the chemical analyses and provided important data for future environmental risk assessments of urban marine sediments.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/metabolismo , Peixes , Genes Reporter , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/toxicidade , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Luciferases/genética , Metais Pesados/análise , Metais Pesados/toxicidade , Noruega , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/análise
8.
Int J Mol Sci ; 22(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070066

RESUMO

Megalin has been proposed as an endocytic receptor for aminoglycosides as well as estrogen and androgen. We aimed to investigate the otoprotective effects of antiandrogens (flutamide, FM) on kanamycin (KM)-induced hearing loss in rats. Rats were divided into four groups. The KM group was administered KM (20 mg/kg/day) for 5 days, while the FM group received FM (15 mg/kg/day) for 10 days. In the KM + FM group, KM and FM (15 mg/kg/day) were simultaneously injected for 5 days and then FM was injected for 5 days. Auditory brainstem responses were measured. Western blotting and/or quantitative reverse transcriptase-polymerase chain reaction were performed for megalin, cytochrome P450 1A1 (Cyp1a1), Cyp1b1, metallothionein 1A (MT1A), MT2A, tumor necrosis factor (TNF)-α, caspase 3, and cleaved caspase 3. The FM + KM group showed attenuated auditory thresholds when compared with the KM group at 4, 8, 16, and 32 kHz (all p < 0.05). The KM + FM group showed lower megalin and Cyp1b1 levels than the KM group (all p < 0.05). The KM + FM group revealed lower MT1A, TNFα, and caspase 3 protein levels, compared with those in the KM group (all p < 0.05). Androgen receptor inhibition protects against cochlear injuries in KM-induced hearing loss rats by attenuating megalin expression, revealing anti-inflammatory and anti-apoptotic effects.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Perda Auditiva Neurossensorial/prevenção & controle , Animais , Antibacterianos/toxicidade , Limiar Auditivo/efeitos dos fármacos , Cóclea/efeitos dos fármacos , Cóclea/patologia , Cóclea/fisiopatologia , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Flutamida/farmacologia , Expressão Gênica/efeitos dos fármacos , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/fisiopatologia , Canamicina/toxicidade , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Metalotioneína/genética , Metalotioneína/metabolismo , Substâncias Protetoras/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
9.
Chem Biodivers ; 18(8): e2100222, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34085382

RESUMO

Yinzhihuang oral liquid (YZH) is a traditional Chinese medicine that has been widely used in Asia to prevent and treat neonatal hyperbilirubinemia, but the published preclinical studies on its anti-hyperbilirubinemia effect are conducted in adult animals, partly due to the lack of preclinical neonatal hyperbilirubinemia animal models. In the present study, we tested six reagents to induce hyperbilirubinemia in neonatal rats, and established two appropriate neonatal hyperbilirubinemia rat models by subcutaneous injection of δ-Aminolevulinic acid (ALA, 200 mg/kg) or novobiocin (NOVO, 200 mg/kg). Oral treatment of YZH (80, 160 and 320 mg/kg) significantly decreased serum conjugated bilirubin levels in ALA-treated neonatal rats and serum unconjugated bilirubin levels in NOVO-treated neonatal rats, respectively. Additionally, pre-treatment of YZH also prevented the increase of serum bilirubin levels in both ALA- and NOVO-treated rats. Mechanistically, YZH significantly up-regulated the mRNA expression of genes involved in hepatic bilirubin disposition (organic anion-transporting polypeptide 1b2, Oatp1b2; multidrug resistance-associated protein 2, Mrp2) and bilirubin conjugation (UDP-glucuronosyltransferase 1a1, Ugt1a1). Additionally, YZH up-regulated the mRNA expression of cytochrome P450 1A1 (Cyp1a1), the target gene of aryl hydrocarbon receptor (AhR), and increased the nuclear protein levels of AhR in livers of neonatal rats. YZH and its two active ingredients, namely baicalin (BCL) and 4'-hydroxyacetophenone (4-HT), up-regulated the mRNA expression of AhR target genes (CYP1A1 and UGT1A1) and increased nuclear protein levels of AhR in HepG2 cells. In conclusion, the present study provides two neonatal hyperbilirubinemia animal models and evaluates the anti-hyperbilirubinemia effect and mechanisms of YZH in neonatal animals.


Assuntos
Medicamentos de Ervas Chinesas/química , Administração Oral , Ácido Aminolevulínico/toxicidade , Animais , Animais Recém-Nascidos , Bilirrubina/sangue , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Células Hep G2 , Humanos , Hiperbilirrubinemia/induzido quimicamente , Hiperbilirrubinemia/tratamento farmacológico , Hiperbilirrubinemia/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Medicina Tradicional Chinesa , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Novobiocina/toxicidade , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
Front Immunol ; 12: 635748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936048

RESUMO

Xenobiotic-mediated activation of the aryl hydrocarbon receptor (AHR) is immunotoxic in a number of immune cell types, with the B cell being a well-established sensitive target. Recent advances have provided evidence that the B cell repertoire is a heterogeneous population, with subpopulations exhibiting vastly different cellular and functional phenotypes. Recent work from our laboratory identified the T cell specific kinase lck as being differentially regulated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which is a potent activator of AHR. While LCK is primarily expressed in T cells, a subset of CD5+ B cells also express LCK. CD5 positivity describes a broad class of B lymphocytes termed innate-like B cells (ILBs) that are critical mediators of innate immunity through constitutive secretion of polyvalent natural immunoglobulin M (IgM). We hypothesized that CD5+ ILBs may be sensitive to AHR-mediated immunotoxicity. Indeed, when CD5+ B cells were isolated from the CD19+ pool and treated with TCDD, they showed increased suppression of the CD40 ligand-induced IgM response compared to CD5- B cells. Further, characterization of the CD5+ population indicated increased basal expression of AHR, AHR repressor (AHRR), and cytochrome p450 family 1 member a1 (CYP1A1). Indeed the levels of AHR-mediated suppression of the IgM response from individual donors strongly correlated with the percentage of the B cell pool that was CD5+, suggesting that CD5+ B cells are more sensitive to AHR-mediated impairment. Together these data highlight the sensitive nature of CD5+ ILBs to AHR activation and provide insight into mechanisms associated with AHR activation in human B cells.


Assuntos
Subpopulações de Linfócitos B/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Antígenos CD5/metabolismo , Imunidade Inata/efeitos dos fármacos , Imunoglobulina M/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/agonistas , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Antígenos CD5/genética , Células Cultivadas , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Humanos , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Fenótipo , Proteína 2 Ligante de Morte Celular Programada 1/genética , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
11.
Aquat Toxicol ; 235: 105815, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33838494

RESUMO

Tris(4-chlorophenyl)methanol (TCPMOH) is a water contaminant with unknown etiology, but is believed to be a byproduct of DDT manufacturing. It is highly persistent in the environment, and bioaccumulates in marine species. TCPMOH has also been measured in human breast milk, which poses a risk for developing infants. However, almost no toxicity data is currently available. In this study, we investigate the hazard posed by developmental TCPMOH exposures using the zebrafish model (Danio rerio). Zebrafish (Danio rerio) embryos were exposed to 0, 0.1, 0.5, 1, or 5 µM TCPMOH beginning at 24 h post fertilization (hpf). Embryonic mortality and incidence of morphological deformities increased in a concentration-dependent manner with TCPMOH exposure. RNA sequencing assessed changes in gene expression associated with acute (4 hour) exposures to 50 nM TCPMOH. Developmental exposure to TCPMOH decreased expression of ahr2, as well as metabolic enzymes cyp1a1, cyp1b1, cyp1c1, cyp1c2, and cyp2y3 (p<0.05). These findings were concordant with decreased Cyp1a1 induction measured by the ethoxyresorufin-O-deethylase (EROD) assay (p<0.05). Pathways associated with xenobiotic metabolism, lipid metabolism, and transcriptional and translational regulation were decreased. Pathways involved in DNA replication and repair, carbohydrate metabolism, and endocrine function were upregulated. Overall, this study demonstrates that TCPMOH is acutely toxic to zebrafish embryos at elevated concentrations.


Assuntos
Compostos de Tritil/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Ecotoxicologia , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Humanos , Inativação Metabólica , Metanol/metabolismo , Ativação Transcricional , Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/genética
12.
Toxicol Appl Pharmacol ; 419: 115502, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33774063

RESUMO

The toxicological manifestation of many pollutants relies upon their binding to the aryl hydrocarbon receptor (AHR), and it follows a cascade of reactions culminating in an elevated expression of cytochrome P450 (CYP) 1 enzymes. CYP1A1 and CYP1B1 are associated with enhanced carcinogenesis when chronically exposed to certain polyaromatic hydrocarbons, and their inhibition may lead to chemoprevention. We evaluated dibenzyl trisulfide (DTS), expressed in the ethnomedical plant, Petiveria alliacea, for such potential chemoprevention. Using recombinant human CYP1A1 and CYP1B1 bactosomes on a fluorogenic assay, we first demonstrated that DTS moderately inhibited both enzymes with half maximal inhibitory concentration (IC50) values of 1.3 ± 0.3 and 1.7 ± 0.3 µM, respectively. Against CYP1A1, DTS was a reversible, competitive inhibitor with an apparent inhibitory constant (Ki) of 4.55 ± 0.37 µM. In silico molecular modeling showed that DTS binds with an affinity of -39.8 kJ·mol-1, situated inside the binding pocket, approximately 4.3 Å away from the heme group, exhibiting interactions with phenylalanine residue 123 (Phe-123), Phe-224, and Phe-258. Lastly, zebrafish (Danio rerio) embryos were exposed to 0.08-0.8 µM DTS from 24 to 96 h post fertilization (hpf) with the in vivo ethoxyresorufin-O-deethylase (EROD) assay, and, at 96 hpf, DTS significantly suppressed EROD CYP1A activity in a dose-dependent manner, with up to 60% suppression in the highest 0.8 µM exposure group. DTS had no impact on gene transcription levels for cyp1a and aryl hydrocarbon receptor 2 (ahr2). In co-exposure experiments, DTS suppressed CYP1A activity induced by both B[a]P and PCB-126, although these reductions were not significant. Taken together, these results demonstrate that DTS is a direct, reversible, competitive inhibitor of the carcinogen-activating CYP1A enzyme, binding in the active site pocket close to the heme site, and shows potential in chemoprevention.


Assuntos
Compostos de Benzil/farmacologia , Citocromo P-450 CYP1A1/antagonistas & inibidores , Citocromo P-450 CYP1B1/antagonistas & inibidores , Inibidores das Enzimas do Citocromo P-450/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Sulfetos/farmacologia , Proteínas de Peixe-Zebra/metabolismo , Ativação Metabólica , Animais , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidade , Compostos de Benzil/metabolismo , Sítios de Ligação , Ligação Competitiva , Domínio Catalítico , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Inibidores das Enzimas do Citocromo P-450/metabolismo , Regulação da Expressão Gênica , Humanos , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidade , Ligação Proteica , Receptores de Hidrocarboneto Arílico/genética , Sulfetos/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
13.
Toxicol Lett ; 344: 58-68, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33727136

RESUMO

Luteolin (5,7,3',4'-tetrahydroxyflavone) belongs to the flavone subclass of flavonoids. Luteolin and its glycosides are present in many botanical families, including edible plants, fruits, and vegetables. While the beneficial properties of luteolin have been widely studied, fewer studies have investigated its toxicity. In the present study, using human lymphoblastoid TK6 cells and our newly developed TK6-derived cell lines that each stably express a single human cytochrome P450 (CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C18, 2C9, 2C19, 2D6, 2E1, 3A4, 3A5, and 3A7), we systematically evaluated luteolin-induced cytotoxicity and genotoxicity, and the role of specific CYPs in the bioactivation of luteolin. Treatments with luteolin for 4-24 h induced cytotoxicity, apoptosis, DNA damage, and chromosome damage in a concentration-dependent manner. Subsequently, we observed that luteolin-induced cytotoxicity and genotoxicity, measured by the high-throughput micronucleus assay, were significantly increased in TK6 cells transduced with CYP1A1 and 1A2. In addition, key apoptosis and DNA damage biomarkers, including cleaved PARP-1, cleaved caspase-3, and phosphorylated histone 2AX (γH2A.X), were all significantly increased in the CYP1A1- and 1A2-expressing cells compared with the empty vector controls. Analysis by LC-MS/MS revealed that TK6 cells biotransformed the majority of luteolin into diosmetin, a less toxic O-methylated flavone, after 24 h; the presence of CYP1A1 and 1A2 partially reversed this process. Altogether, these results indicate that metabolism by CYP1A1 and 1A2 enhanced the toxicity of luteolin in vitro. Our results further support the utility of our TK6 cell system for identification of the specific CYPs responsible for chemical bioactivation and toxicity potential.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Luteolina/toxicidade , Trifosfato de Adenosina/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Linhagem Celular , Sobrevivência Celular , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Dano ao DNA/efeitos dos fármacos , Humanos , Luteolina/química , Micronúcleos com Defeito Cromossômico , Estrutura Molecular , Mutagênicos
14.
Chem Biol Interact ; 338: 109428, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647240

RESUMO

Camostat mesylate, a potent inhibitor of the human transmembrane protease, serine 2 (TMPRSS2), is currently under investigation for its effectiveness in COVID-19 patients. For its safe application, the risks of camostat mesylate to induce pharmacokinetic drug-drug interactions with co-administered drugs should be known. We therefore tested in vitro the potential inhibition of important efflux (P-glycoprotein (P-gp, ABCB1), breast cancer resistance protein (BCRP, ABCG2)), and uptake transporters (organic anion transporting polypeptides OATP1B1, OATP1B3, OATP2B1) by camostat mesylate and its active metabolite 4-(4-guanidinobenzoyloxy)phenylacetic acid (GBPA). Transporter inhibition was evaluated using fluorescent probe substrates in transporter over-expressing cell lines and compared to the respective parental cell lines. Moreover, possible mRNA induction of pharmacokinetically relevant genes regulated by the nuclear pregnane X receptor (PXR) and aryl hydrocarbon receptor (AhR) was analysed in LS180 cells by quantitative real-time PCR. The results of our study for the first time demonstrated that camostat mesylate and GBPA do not relevantly inhibit P-gp, BCRP, OATP1B1 or OATP1B3. Only OATP2B1 was profoundly inhibited by GBPA with an IC50 of 11 µM. Induction experiments in LS180 cells excluded induction of PXR-regulated genes such as cytochrome P450 3A4 (CYP3A4) and ABCB1 and AhR-regulated genes such as CYP1A1 and CYP1A2 by camostat mesylate and GBPA. Together with the summary of product characteristics of camostat mesylate indicating no inhibition of CYP1A2, 2C9, 2C19, 2D6, and 3A4 in vitro, our data suggest a low potential of camostat mesylate to act as a perpetrator in pharmacokinetic drug-drug interactions. Only inhibition of OATP2B1 by GBPA warrants further investigation.


Assuntos
Interações Medicamentosas , Ésteres/metabolismo , Guanidinas/metabolismo , Inibidores de Serino Proteinase/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Ésteres/química , Ésteres/farmacologia , Guanidinas/química , Guanidinas/farmacologia , Humanos , Transportadores de Ânions Orgânicos/antagonistas & inibidores , Transportadores de Ânions Orgânicos/metabolismo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Inibidores de Serino Proteinase/química , Inibidores de Serino Proteinase/farmacologia
15.
Int J Mol Sci ; 22(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562118

RESUMO

The aryl hydrocarbon receptor (AHR) is a ligand-activated signaling molecule expressed in many cell types, including triple-negative and non-triple-negative breast cancer cells. It affects breast cancer growth and crosstalk with estrogen receptor signaling. Normally, this receptor is degraded shortly after ligand activation via the 26S proteasome. Here, we report that AHR undergoes chaperone-mediated autophagy in MDA-MB-468 triple-negative breast cancer cells. This lysosomal degradation of AHR exhibits the following characteristics: (1) it is triggered by 6 amino-nicotinamide, starvation, and piperazinylpyrimidine compound Q18; (2) it is not observed in non-triple-negative breast cancer cells (MCF-7, T47D, and MDA-MB-361); (3) it can be inhibited by progesterone receptor B but not estrogen receptor alpha; (4) it can be reversed by chloroquine but not MG132; (5) it requires LAMP2A; and (6) it involves AHR-HSC70 and AHR-LAMP2A interactions. The NEKFF sequence localized at amino acid 558 of human AHR appears to be a KFERQ-like motif of chaperone-mediated autophagy, responsible for the LAMP2A-mediated AHR protein degradation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Autofagia Mediada por Chaperonas/fisiologia , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Proteólise , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Sequência de Aminoácidos , Linhagem Celular Tumoral , Cloroquina/farmacologia , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Receptor alfa de Estrogênio/metabolismo , Humanos , Leupeptinas/farmacologia , Lisossomos/metabolismo , Células MCF-7 , Interferência de RNA , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transdução de Sinais/fisiologia
16.
Commun Biol ; 4(1): 55, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420418

RESUMO

Cytochrome P450 (CYP) heme monooxygenases require two electrons for their catalytic cycle. For mammalian microsomal CYPs, key enzymes for xenobiotic metabolism and steroidogenesis and important drug targets and biocatalysts, the electrons are transferred by NADPH-cytochrome P450 oxidoreductase (CPR). No structure of a mammalian CYP-CPR complex has been solved experimentally, hindering understanding of the determinants of electron transfer (ET), which is often rate-limiting for CYP reactions. Here, we investigated the interactions between membrane-bound CYP 1A1, an antitumor drug target, and CPR by a multiresolution computational approach. We find that upon binding to CPR, the CYP 1A1 catalytic domain becomes less embedded in the membrane and reorients, indicating that CPR may affect ligand passage to the CYP active site. Despite the constraints imposed by membrane binding, we identify several arrangements of CPR around CYP 1A1 that are compatible with ET. In the complexes, the interactions of the CPR FMN domain with the proximal side of CYP 1A1 are supplemented by more transient interactions of the CPR NADP domain with the distal side of CYP 1A1. Computed ET rates and pathways agree well with available experimental data and suggest why the CYP-CPR ET rates are low compared to those of soluble bacterial CYPs.


Assuntos
Membrana Celular/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Transporte de Elétrons , Humanos , Simulação de Dinâmica Molecular , Domínios Proteicos
17.
Toxicol Lett ; 341: 1-10, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429014

RESUMO

Piscine cytochrome P450 (CYP) enzymes play an important role in the metabolism of xenobiotics. Xenobiotics often act as inducers of CYP1A1 and CYP3A expression and activity in fish. We compared constitutive mRNA expression of CYP1A1, CYP3A27, and CYP3A45 and catalytic activity of CYP1A (7-ethoxyresorufin-O-deethylation, EROD) and CYP3A-like (benzyloxy-4-trifluoromethylcoumarin-O-debenzyloxylation, BFCOD) enzymes in the following six rainbow trout tissues: liver, gill, heart, brain, intestine, and gonad. mRNA expression and activity were present in all investigated tissues. The CYP1A1 mRNA expression was higher in the liver, gill, heart, and brain compared to gonad and intestine. The intestine was the main site of CYP3A27 and CYP3A45 expression. The highest EROD and BFCOD activity was observed in liver tissue followed in descending order by heart, brain, gill, intestine, and gonad. Such differences might be related to the role of CYP physiological functions in the specific tissue. Rainbow trout exposure to 50 mg/kg of ß-naphthoflavone for 48 h resulted in a 7.5- and 5.9-fold increase in liver EROD and BFCOD activity, respectively. In vitro EROD activity inhibition with ellipticine showed tissue-specific inhibition, while ketoconazole decreased BFCOD activity by 50-98 % in all tissues. Further studies are needed to identify all CYP isoforms that are responsible for these activities and modes of regulation.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP3A/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Oncorhynchus mykiss/metabolismo , Animais , Encéfalo/enzimologia , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP3A/genética , Feminino , Brânquias/enzimologia , Intestinos/enzimologia , Fígado/enzimologia , Masculino , Miocárdio/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Caracteres Sexuais
18.
Biochem J ; 478(2): 377-388, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33394027

RESUMO

P450 and heme oxygenase-1 (HO-1) receive their necessary electrons by interaction with the NADPH-cytochrome P450 reductase (POR). As the POR concentration is limiting when compared with P450 and HO-1, they must effectively compete for POR to function. In addition to these functionally required protein-protein interactions, HO-1 forms homomeric complexes, and several P450s have been shown to form complexes with themselves and with other P450s, raising the question, 'How are the HO-1 and P450 systems organized in the endoplasmic reticulum?' Recently, CYP1A2 was shown to associate with HO-1 affecting the function of both proteins. The goal of this study was to determine if CYP1A1 formed complexes with HO-1 in a similar manner. Complex formation among POR, HO-1, and CYP1A1 was measured using bioluminescence resonance energy transfer, with results showing HO-1 and CYP1A1 form a stable complex that was further stabilized in the presence of POR. The POR•CYP1A1 complex was readily disrupted by the addition of HO-1. CYP1A1 also was able to affect the POR•HO-1 complex, although the effect was smaller. This interaction between CYP1A1 and HO-1 also affected function, where the presence of CYP1A1 inhibited HO-1-mediated bilirubin formation by increasing the KmPOR•HO-1 without affecting the Vmaxapp. In like manner, HO-1 inhibited CYP1A1-mediated 7-ethoxyresorufin dealkylation by increasing the KmPOR•CYP1A1. Based on the mathematical simulation, the results could not be explained by a model where CYP1A1 and HO-1 simply compete for POR, and are consistent with the formation of a stable CYP1A1•HO-1 complex that affected the functional characteristics of both moieties.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Heme Oxigenase-1/metabolismo , Técnicas de Transferência de Energia por Ressonância de Bioluminescência , Citocromo P-450 CYP1A1/química , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Heme Oxigenase-1/química , Humanos , Domínios e Motivos de Interação entre Proteínas
19.
Ecotoxicol Environ Saf ; 209: 111820, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33385678

RESUMO

The objective of this study was to investigate the influence of deltamethrin (DLM)on brain function and to find whether DLM-induced neurotoxicity is prevented by the treatment with cinnamon oil. Four groups of ten Wistar albino male rats each were used. Group I (control) received saline only. Group II received cinnamon oil alone at 0.5 mg/kg B.W. intraperitonally, whereas Group III received orally DLM alone at 6 mg/kg B.W. Groups IV was treated with cinnamon oil plus DLM for 21 days to induce neurotoxicity. Rat behaviour, brain acetylcholine esterase (AChE), serotonin, oxidative stress profile were assessed. Serum sampling for the assessment of corticosterone concentration was also carried out. Finally, we demonstrate the gene expression of CYP1A1 and iNOS and the histological picture of the brain. Considering the behaviour assessment, DLM administration alone caused neurobehavioral deficits manifested by anxiety-like behavior which represented ina marked decrease in the sleeping frequency and duration, and marked increase the digging frequency and a wake non-active behavior duration. Moreover, the open field result showed a significant decrease in central square entries and duration. The neurochemical analysis revealed that DLM significantly suppressed AChE activity and elevated serotonin and corticosterone concentrations. Furthermore, results revealed thatthe brain reduced glutathione (GSH) content, superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration were significantly altered in DLM treated rats. Neurochemical disturbances were confirmed by histopathological changes in the brain. Furthermore, DLM up-regulates the mRNA expression of brain CYP1A1 and iNOS. Co-treatment with cinnamon oil exhibited significant improvement in behavioural performance and the brain antioxidant capacities with an increase in AChE activity and diminished the concentration of serotonin, serum corticosterone and MDA. Cinnamon oil treatment resulted in down-regulation of CYP1A1 and iNOS and improve the histologically picture. In conclusion, cinnamon oil ameliorated DLM-induced neurotoxicity through preventing oxidative stress-induced genotoxicity and apoptosis of brain in rats.


Assuntos
Cinnamomum zeylanicum , Citocromo P-450 CYP1A1/metabolismo , Inseticidas/toxicidade , Neurotransmissores/farmacologia , Nitrilas/toxicidade , Óleos Voláteis/farmacologia , Piretrinas/toxicidade , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Glutationa/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
20.
Arch Pharm Res ; 44(1): 63-83, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33484438

RESUMO

Human cytochrome P450 enzymes (CYPs) play a critical role in various biological processes and human diseases. CYP1 family members, including CYP1A1, CYP1A2, and CYP1B1, are induced by aryl hydrocarbon receptors (AhRs). The binding of ligands such as polycyclic aromatic hydrocarbons activates the AhRs, which are involved in the metabolism (including oxidation) of various endogenous or exogenous substrates. The ligands that induce CYP1 expression are reported to be carcinogenic xenobiotics. Hence, CYP1 enzymes are correlated with the pathogenesis of cancers. Various endogenous substrates are involved in the metabolism of steroid hormones, eicosanoids, and other biological molecules that mediate the pathogenesis of several human diseases. Additionally, CYP1s metabolize and activate/inactivate therapeutic drugs, especially, anti-cancer agents. As the metabolism of drugs determines their therapeutic efficacy, CYP1s can determine the susceptibility of patients to some drugs. Thus, understanding the role of CYP1s in diseases and establishing novel and efficient therapeutic strategies based on CYP1s have piqued the interest of the scientific community.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Xenobióticos/farmacocinética , Animais , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1B1/genética , Modelos Animais de Doenças , Predisposição Genética para Doença , Humanos , Ligantes , Receptores de Hidrocarboneto Arílico/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...