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1.
Curr Protein Pept Sci ; 20(10): 976-983, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31362653

RESUMO

Diabetes mellitus (DM) has become an increasingly common disease with high disability and mortality rates. Diabetes complications are the main cause of diabetes death and about 50% of diabetic patients died from heart disease in developed countries reported by World Health Organization. Diabetic cardiomyopathy (DCM) has been considered as a high incidence and serious complication of DM and plays a key role in the incidence and development of diabetes related heart failure. Metabolism dysregulation is regarded as an important and earlier factor occurred in the pathogenesis of DCM. Insulin resistance, oxidative stress, inflammation and mitochondrial dysfunction also contribute to the development of DCM. Farnesoid X Receptor (FXR) is a member of nuclear receptor superfamily, and plays a critical role in regulating lipid and glucose metabolism, oxidative stress and inflammation. FXR is activated by primary bile acids (BAs) such as chenodeoxycholic acid, cholic acid and synthetic agonists such as obeticholic acid. BAs are the main active ingredients of many natural products and traditional medicines, especially bile or gallstones in animals, such as calculus bovis. Due to the regulatory effect of FXR on glucose and lipid metabolism, oxidative stress and inflammation, the treatment of BAs and FXR agonists for metabolic syndrome and DCM have gained more attention. This review will focus on the pathogenesis of diabetic cardiomyopathy and the regulatory effect of BAs and FXR on DCM.


Assuntos
Ácidos e Sais Biliares/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Cardiomiopatias Diabéticas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Produtos Biológicos/química , Produtos Biológicos/metabolismo , Produtos Biológicos/uso terapêutico , Biomarcadores/metabolismo , Glucose/metabolismo , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos
2.
Chem Biol Interact ; 311: 108794, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31421115

RESUMO

Acanthoic acid (AA) is a pimaradiene diterpene isolated from Acanthopanax koreanum Nakai (Araliaceae), with anti-inflammatory and hepatic-protective effects. The present study intended to reveal the effect and mechanism of AA on nonalcoholic fatty liver disease (NAFLD) associated with lipid accumulation by activating Farnesoid X receptor (FXR) and liver X receptors (LXRs) signaling. C57BL/6 mice were received a modified Lieber-DeCarli diet with 71% high-fat (L-D) and treated with AA (20 and 40 mg/kg) or equal volume of saline for 12 weeks. The regulation of AA on lipid accumulation was also detected in pro-steatotic stimulated AML12 cells with palmitic acid (PA). When L-D diet-fed mice were treated with AA, loss in body weight, liver index, and liver lipid droplet were observed along with reduced triglyceride (TG) and serum transaminase. Furthermore, AA decreased sterol regulatory element binding protein 1 (SREBP-1) and target genes expression, regulated PPARα and PPARγ expressions, ameliorated hepatic fibrosis markers, enhanced hepatic FXR and LXR, and regulated AMPK-LKB1 and SIRT1 signaling pathway. Moreover, AA attenuated lipid accumulation via FXR and LXR activation in steatotic AML-12 cells, which was confirmed by guggulsterones (FXR antagonist) or GW3965 (LXR agonist). Activation of FXR and LXR signaling caused by AA might increase AMPK-SIRT1 signaling and then contribute to modulating lipid accumulation and fatty acid synthesis, which suggested that activated FXR-LXR axis by AA represented an effective strategy for relieving NAFLD.


Assuntos
Diterpenos/farmacologia , Lipogênese/efeitos dos fármacos , Receptores X do Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Dieta Hiperlipídica , Diterpenos/química , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores X do Fígado/agonistas , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR alfa/genética , PPAR alfa/metabolismo , Ácido Palmítico/farmacologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/sangue
3.
Cell Physiol Biochem ; 53(2): 366-387, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31385665

RESUMO

BACKGROUND/AIMS: The extracellular signal-regulated kinases (ERK) 1 and 2 (ERK1/2) are members of the mitogen-activated protein kinase (MAPK) family. Upon stimulation, these kinases translocate from the cytoplasm to the nucleus, where they induce physiological processes such as proliferation and differentiation. The mechanism of translocation of this kinase involves phosphorylation of two Ser residues within a nuclear translocation signal (NTS), which allows binding to importin7 and a subsequent penetration via nuclear pores. However, the regulation of this process and the protein kinases involved are not yet clear. METHODS: To answer this point we developed specific anti phospho-SPS antibody, used this and other antibodies in Western blots and crystalized the phospho-mimetic mutated ERK. RESULTS: Here we show that the phosphorylation of both Ser residues is mediated mainly by casein kinase 2 (CK2) and that active ERK may assist in the phosphorylation of the N-terminal Ser. We also demonstrate that the phosphorylation is dependent on the release of ERK from cytoplasmic anchoring proteins. Crystal structure of the phosphomimetic ERK revealed that the NTS phosphorylation creates an acidic patch in ERK. Our model is that in resting cells ERK is bound to cytoplasmic anchors, which prevent its NTS phosphorylation. Upon stimulation, phosphorylation of the ERK TEY domain releases ERK and allows phosphorylation of its NTS by CK2 and active ERK to generate a negatively charged patch in ERK, binding to importin 7 and nuclear translocation. CONCLUSION: These results provide an important role of CK2 in regulating nuclear ERK activities.


Assuntos
Núcleo Celular/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Transporte Ativo do Núcleo Celular , Caseína Quinase II/metabolismo , Linhagem Celular , Humanos , Carioferinas/metabolismo , Fosforilação , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/metabolismo
4.
Environ Pollut ; 253: 889-898, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349198

RESUMO

Atrazine (ATR), one of the most widely used pesticides in agricultural production, are gradually concerned due to potential ecosystem and health risks. Further, the induction of ATR nephrotoxicity and detoxification response is still unknown. To evaluate ATR-induced nephrotoxicity, quails were treated with 0, 50, 250 or 500 mg/kg ATR by gavage administration for 45 days. Histopathology indicated that ATR exposure caused renal tubular epithelial cell swelling and endoplasmic reticulum degeneration, suggesting that ATR exposure causes renal impairment even renal diseases. Notably, ATR interfered cytochrome P450 system (CYP450s) homeostasis by enhancing contents or activities of CYP450s (total CYP450, Cyt b5, AH, APND, NCR and ERND) and the expression of CYP450 isoforms (CYP1A, CYP1B, CYP2C and CYP3A). ATR triggered phase II detoxifying reaction, reflected by the elevated GSH level, GST activity and the up-regulation of GST isoforms (GSTa, GSTa3 and GSTt1) and GSH synthetase (GCLC). Moreover, ABC transporters were activated to expel ATR from the body by increasing expression of MRP1 and P-GP gene. Accompanying these alterations, the nuclear receptors (AHR, CAR and PXR) were activated by ATR in a dose-dependent manner. Analysis results of present study demonstrated that the induction of phase II detoxifying enzyme system and ABC transporters could be modulated by nuclear receptors response and CYP450s disturbance in low-dose ATR-treated quail. In conclusion, all data suggested that nuclear receptors AHR-mediated detoxification pathway was involved in ATR-induced nephrotoxicity. These results provided new evidence about the nephrotoxic effects of ATR on the response of biotransformation and detoxification system.


Assuntos
Atrazina/toxicidade , Coturnix/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Xenobióticos/toxicidade , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Homeostase/efeitos dos fármacos , Inativação Metabólica , Codorniz , Receptores Citoplasmáticos e Nucleares/metabolismo , Xenobióticos/metabolismo
5.
Eur J Med Chem ; 180: 224-237, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31306909

RESUMO

Cytotoxic effects of (R)-4'-methylklavuzon were investigated on hepatocellular carcinoma cells (HuH-7 and HepG2) and HuH-7 EpCAM+/CD133+ cancer stem cells. IC50 of (R)-4'-methylklavuzon was found as 1.25 µM for HuH-7 parental cells while it was found as 2.50 µM for HuH-7 EpCAM+/CD133+ cancer stem cells. (R)-4'-methylklavuzon tended to show more efficient in vitro cytotoxicity with its lower IC50 values on hepatocellular carcinoma cell lines compared to its lead molecule, goniothalamin and FDA-approved drugs, sorafenib and regorafenib. Cell-based Sirtuin/HDAC enzyme activity measurements revealed that endogenous Sirtuin/HDAC enzymes were reduced by 40% compared to control. SIRT1 protein levels were upregulated indicating triggered DNA repair mechanism. p53 was overexpressed in HepG2 cells. (R)-4'-methylklavuzon inhibited CRM1 protein providing increased retention of p53 and RIOK2 protein in the nucleus. HuH-7 parental and EpCAM+/CD133+ cancer stem cell spheroids lost intact morphology. 3D HepG2 spheroid viabilities were decreased in a correlation with upregulation in p53 protein levels.


Assuntos
Antígeno AC133/antagonistas & inibidores , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Molécula de Adesão da Célula Epitelial/antagonistas & inibidores , Carioferinas/antagonistas & inibidores , Neoplasias Hepáticas/tratamento farmacológico , Naftalenos/farmacologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Sirtuína 1/antagonistas & inibidores , Antígeno AC133/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Molécula de Adesão da Célula Epitelial/metabolismo , Células Hep G2 , Humanos , Carioferinas/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Estrutura Molecular , Naftalenos/síntese química , Naftalenos/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Sirtuína 1/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
6.
Life Sci ; 232: 116638, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31288013

RESUMO

AIMS: High-fat diet (HFD)-induced obesity resulting in cholesterol accumulation is one of the common pathogenic factors for lipids metabolic disorders. However, the potential mechanisms about cholesterol accumulation during obesity are still not clearly identified. Bile acids (BAs) as the natural ligands of farnesoid x receptor (Fxr) are demonstrated that can regulate the relevant enzymes and transporters at transcriptional level to determine the cholesterol homeostasis. Here, we explored the underlying mechanisms of hepatic cholesterol accumulation in HFD-induced obesity rats via the BAs-Fxr-enzymes/transporters signaling pathways. MATERIALS AND METHODS: BAs and cholesterol levels as well as mRNA expressions of enzymes, transporters and nuclear receptors involving in cholesterol homeostasis in liver and ileum tissue were evaluated in 4-week HFD-induced obesity rats. KEY FINDINGS: HFD promoted BAs intestine passive absorption to increase the concentrations of BAs especially the chenodeoxycholic acids (CDCAs) in ileum of HFD-induced obesity rats. The increased CDCAs concentrations activated Fxr-Fgf15 pathway in ileum to result in the mRNA expression of Cyp7a1 in liver down-regulation, which inhibited cholesterol metabolizing into primary BAs to contribute to the cholesterol level increase in liver tissue in HFD-induced obesity rats. SIGNIFICANCE: The hepatic cholesterol accumulation should be ascribed to the activation of ileum Fxr-Fgf15 pathway by the increased BAs passive absorption into ileal enterocytes under the condition of rats fed with HFD, which inhibited hepatic Cyp7a1 gene transcription to reduce metabolic elimination of cholesterol. Moreover, these findings are expected to provide a cue for the treatment of cholesterol metabolism disorders in obesity patient.


Assuntos
Colesterol 7-alfa-Hidroxilase/antagonistas & inibidores , Dieta Hiperlipídica , Fatores de Crescimento de Fibroblastos/metabolismo , Íleo/metabolismo , Fígado/metabolismo , Obesidade/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Células CACO-2 , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilase/metabolismo , Humanos , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Obesidade/enzimologia , Ratos , Ratos Wistar , Transdução de Sinais
7.
J Agric Food Chem ; 67(32): 8868-8874, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31319027

RESUMO

Chenodeoxycholic acid (CDCA), a primary bile acid, has been demonstrated to play important roles as a signaling molecule in various physiology functions. However, the role of CDCA in regulating intestinal barrier function remains largely unknown. This study aimed to investigate the effects of CDCA on the lipopolysaccharide (LPS)-impaired intestinal epithelial barrier function and explore the underlying mechanisms. In IPEC-J2 cells, CDCA reversed the LPS-induced increase in transepithelial electrical resistance and decrease in tight junction protein expression. In addition, we found that farnesoid X receptor (FXR) but not Takeda G-protein receptor 5 was responsible for the CDCA-improved epithelial barrier function impaired by LPS. Furthermore, CDCA blocked LPS-induced activation of the myosin light chain kinase (MLCK) pathway in a FXR-dependent manner and elicited similar effects to MLCK inhibition. In mice, CDCA supplementation restored LPS-induced elevation of intestinal permeability and MLCK expression and reduction of tight junction protein expression, thus alleviating LPS-induced intestinal barrier impairment. In conclusion, CDCA protected against the LPS-induced impairment of the intestinal epithelial barrier function via the FXR-MLCK pathway.


Assuntos
Ácido Quenodesoxicólico/administração & dosagem , Enteropatias/tratamento farmacológico , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/efeitos adversos , Quinase de Cadeia Leve de Miosina/metabolismo , Substâncias Protetoras/administração & dosagem , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Células CACO-2 , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Enteropatias/induzido quimicamente , Enteropatias/genética , Enteropatias/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Quinase de Cadeia Leve de Miosina/genética , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/efeitos dos fármacos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/genética , Junções Íntimas/metabolismo
8.
Genes Dev ; 33(15-16): 1083-1094, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31296559

RESUMO

The orphan nuclear receptor SHP (small heterodimer partner) is a well-known transcriptional corepressor of bile acid and lipid metabolism in the liver; however, its function in other tissues is poorly understood. Here, we report an unexpected role for SHP in the exocrine pancreas as a modulator of the endoplasmic reticulum (ER) stress response. SHP expression is induced in acinar cells in response to ER stress and regulates the protein stability of the spliced form of X-box-binding protein 1 (XBP1s), a key mediator of ER stress response. Loss of SHP reduces XBP1s protein level and transcriptional activity, which in turn attenuates the ER stress response during the fasting-feeding cycle. Consequently, SHP-deficient mice also are more susceptible to cerulein-induced pancreatitis. Mechanistically, we show that SHP physically interacts with the transactivation domain of XBP1s, thereby inhibiting the polyubiquitination and degradation of XBP1s by the Cullin3-SPOP (speckle-type POZ protein) E3 ligase complex. Together, our data implicate SHP in governing ER homeostasis and identify a novel posttranslational regulatory mechanism for the key ER stress response effector XBP1.


Assuntos
Estresse do Retículo Endoplasmático/genética , Proteólise , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína 1 de Ligação a X-Box/metabolismo , Células Acinares/metabolismo , Animais , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Pâncreas Exócrino/metabolismo , Pancreatite/genética , Processamento de Proteína , Estabilidade Proteica , Receptores Citoplasmáticos e Nucleares/deficiência , Receptores Citoplasmáticos e Nucleares/genética , Ubiquitinação/genética
9.
Nat Commun ; 10(1): 2915, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266946

RESUMO

The bile acid-sensing transcription factor farnesoid X receptor (FXR) regulates multiple metabolic processes. Modulation of FXR is desired to overcome several metabolic pathologies but pharmacological administration of full FXR agonists has been plagued by mechanism-based side effects. We have developed a modulator that partially activates FXR in vitro and in mice. Here we report the elucidation of the molecular mechanism that drives partial FXR activation by crystallography- and NMR-based structural biology. Natural and synthetic FXR agonists stabilize formation of an extended helix α11 and the α11-α12 loop upon binding. This strengthens a network of hydrogen bonds, repositions helix α12 and enables co-activator recruitment. Partial agonism in contrast is conferred by a kink in helix α11 that destabilizes the α11-α12 loop, a critical determinant for helix α12 orientation. Thereby, the synthetic partial agonist induces conformational states, capable of recruiting both co-repressors and co-activators leading to an equilibrium of co-activator and co-repressor binding.


Assuntos
Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/química , Animais , Linhagem Celular , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Humanos , Ligações de Hidrogênio , Ligantes , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Conformação Proteica em alfa-Hélice , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
10.
Eur J Med Chem ; 179: 84-99, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247375

RESUMO

The DNA alkylating prodrug cyclophosphamide (CPA), alone or in combination with other agents, is one of the most commonly used anti-cancer agents. As a prodrug, CPA is activated by cytochrome P450 2B6 (CYP2B6), which is transcriptionally regulated by the human constitutive androstane receptor (hCAR). Therefore, hCAR agonists represent novel sensitizers for CPA-based therapies. Among known hCAR agonists, compound 6-(4-chlorophenyl)imidazo-[2,1-b]thiazole-5-carbaldehyde-O-(3,4-dichlorobenzyl)oxime (CITCO) is the most potent and broadly utilized in biological studies. Through structural modification of CITCO, we have developed a novel compound DL5016 (32), which has an EC50 value of 0.66 µM and EMAX value of 4.9 when activating hCAR. DL5016 robustly induced the expression of hCAR target gene CYP2B6, at both the mRNA and protein levels, and caused translocation of hCAR from the cytoplasm to the nucleus in human primary hepatocytes. The effects of DL5016 were highlighted by dramatically enhancing the efficacy of CPA-based cytotoxicity to non-Hodgkin lymphoma cells.


Assuntos
Antineoplásicos/farmacologia , Ciclofosfamida/farmacologia , Linfoma não Hodgkin/tratamento farmacológico , Pró-Fármacos/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclofosfamida/síntese química , Ciclofosfamida/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Estrutura Molecular , Pró-Fármacos/síntese química , Pró-Fármacos/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
11.
Nat Commun ; 10(1): 2514, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175293

RESUMO

The type II nuclear receptors (NRs) function as heterodimeric transcription factors with the retinoid X receptor (RXR) to regulate diverse biological processes in response to endogenous ligands and therapeutic drugs. DNA-binding specificity has been proposed as a primary mechanism for NR gene regulatory specificity. Here we use protein-binding microarrays (PBMs) to comprehensively analyze the DNA binding of 12 NR:RXRα dimers. We find more promiscuous NR-DNA binding than has been reported, challenging the view that NR binding specificity is defined by half-site spacing. We show that NRs bind DNA using two distinct modes, explaining widespread NR binding to half-sites in vivo. Finally, we show that the current models of NR specificity better reflect binding-site activity rather than binding-site affinity. Our rich dataset and revised NR binding models provide a framework for understanding NR regulatory specificity and will facilitate more accurate analyses of genomic datasets.


Assuntos
DNA/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores X Retinoide/metabolismo , Proteínas de Ligação a DNA , Humanos , Receptores X do Fígado , Mutagênese Sítio-Dirigida , Receptores Ativados por Proliferador de Peroxissomo , Receptor de Pregnano X , Receptores de Calcitriol , Receptores do Ácido Retinoico , Receptores dos Hormônios Tireóideos
12.
Food Chem Toxicol ; 131: 110576, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31199990

RESUMO

Ivermectin, a member of the avermectins, is one of the most used anti-parasitic agents, and acts by binding to glutamate-gated chloride channels in invertebrate nerve cells. There is limited information, however, on the effects of ivermectin in non-neural cell, such as adipocytes. The present work aimed to investigate the role of ivermectin in adipogenesis using 3T3-L1 preadipocytes. Ivermectin inhibited the differentiation of preadipocytes and triglyceride (TG) accumulation. In particular, the treatment of ivermectin at the middle to late adipogenic differentiation period (day 2-8) was correlated with the inhibition of fat accumulation. Ivermectin treatment also significantly modulated the mRNA expression of key markers in adipogenesis, fatty acid synthesis, uptake, and oxidation, and enhanced the gene expression of two subunits of the glycine receptor (GlyR). Specifically, the protein levels of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPα), and acetyl-CoA carboxylase (ACC) were reduced. Interestingly, the suppression of TG accumulation by ivermectin was partially abolished by rosiglitazone, a specific PPARγ agonist, but Z-guggulsterone, a selective FXR antagonist, failed to rescue the ivermectin-induced effect on adipogenesis. Lastly, ivermectin prevented adipogenesis induced by permethrin and fipronil. In conclusion, ivermectin inhibits adipogenesis of 3T3-L1 preadipocytes partially via PPARγ & GlyR-dependent, but not FXR-dependent, pathway.


Assuntos
Adipogenia/efeitos dos fármacos , Antiparasitários/farmacologia , Ivermectina/farmacologia , Triglicerídeos/metabolismo , Células 3T3-L1 , Animais , Diferenciação Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Camundongos , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores da Glicina/metabolismo
13.
Handb Exp Pharmacol ; 256: 111-136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31161298

RESUMO

In this chapter we provide an exhaustive overview of the binding modes of bile acid (BA) and non-BA ligands to the nuclear farnesoid X receptor (FXR) and the G-protein bile acid receptor 1 (GPBAR1). These two receptors play a key role in many diseases related to lipid and glucose disorders, thus representing promising pharmacological targets. We pay particular attention to the chemical and structural features of the ligand-receptor interaction, providing guidelines to achieve ligands endowed with selective or dual activity towards the receptor and paving the way to future drug design studies.


Assuntos
Ácidos e Sais Biliares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Desenho de Drogas , Humanos , Ligantes
14.
Toxicol Lett ; 313: 1-10, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170421

RESUMO

The constitutive androstane receptor(CAR) activation is connected with mitogenic effects leading to liver hyperplasia and tumorigenesis in rodents. CAR activators, including phenobarbital, are considered rodent non-genotoxic carcinogens. Recently, trans-3,4,5,4´-tetramethoxystilbene(TMS), a potential anticancer drug (DMU-212), have been shown to alleviate N-nitrosodiethylamine/phenobarbital-induced liver carcinogenesis. We studied whether TMS inhibits mouse Car to protect from the PB-induced tumorigenesis. Unexpectedly, we identified TMS as a murine CAR agonist in reporter gene experiments, in mouse hepatocytes, and in C57BL/6 mice in vivo. TMS up-regulated Car target genes Cyp2b10, Cyp2c29 and Cyp2c55 mRNAs, but down-regulated expression of genes involved in gluconeogenesis and lipogenesis. TMS did not change or down-regulate genes involved in liver proliferation or apoptosis such as Mki67, Foxm1, Myc, Mcl1, Pcna, Bcl2, or Mdm2, which were up-regulated by another Car ligand TCPOBOP. TMS did not increase liver weight and had no significant effect on Ki67 and Pcna labeling indices in mouse liver in vivo. In murine hepatic AML12 cells, we confirmed a Car-independent proapoptotic effect of TMS. We conclude that TMS is a Car ligand with limited effects on hepatocyte proliferation, likely due to promoting apoptosis in mouse hepatic cells, while controlling Car target genes involved in xenobiotic and endobiotic metabolism.


Assuntos
Anticarcinógenos/farmacologia , Proliferação de Células/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Neoplasias Hepáticas/prevenção & controle , Fígado/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/agonistas , Estilbenos/farmacologia , Animais , Anticarcinógenos/metabolismo , Apoptose/efeitos dos fármacos , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Sítios de Ligação , Família 2 do Citocromo P450/genética , Família 2 do Citocromo P450/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Gluconeogênese/genética , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Fígado/metabolismo , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Ligação Proteica , Piridinas/farmacologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Esteroide Hidroxilases/genética , Esteroide Hidroxilases/metabolismo , Estilbenos/metabolismo
15.
Dokl Biochem Biophys ; 485(1): 138-140, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31201635

RESUMO

To study the mechanisms of transcriptional regulation, a convenient experimental approach is to use the artificial chimeric constructs carrying the regulatory elements of interest. In the present work, we describe the creation and characterization of a novel genetic construct that makes it possible to study the transcriptional regulation of the early-late gene of the ecdysone cascade. Using the data of genome-wide experiments, we have isolated the main regulatory region of the hr4 gene, which was successfully used to create a chimeric reporter construct expressing a fluorescent protein upon the treatment with the ecdysone hormone. This reporter system can be used to study the mechanisms of the ecdysone response, both in cell culture and in tissues, at various stages of the Drosophila development.


Assuntos
Proteínas de Drosophila , Ecdisona/metabolismo , Genes Reporter , Receptores Citoplasmáticos e Nucleares , Transcrição Genética , Animais , Linhagem Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Estudo de Associação Genômica Ampla , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
16.
Int J Mol Sci ; 20(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083458

RESUMO

To appraise how evolutionary processes, such as gene duplication and loss, influence an organism's xenobiotic sensitivity is a critical question in toxicology. Of particular importance are gene families involved in the mediation of detoxification responses, such as members of the nuclear receptor subfamily 1 group I (NR1I), the pregnane X receptor (PXR), and the constitutive androstane receptor (CAR). While documented in multiple vertebrate genomes, PXR and CAR display an intriguing gene distribution. PXR is absent in birds and reptiles, while CAR shows a tetrapod-specific occurrence. More elusive is the presence of PXR and CAR gene orthologs in early branching and ecologically-important Chondrichthyes (chimaeras, sharks and rays). Therefore, we investigated various genome projects and use them to provide the first identification and functional characterization of a Chondrichthyan PXR from the chimaera elephant shark (Callorhinchus milii, Holocephali). Additionally, we substantiate the targeted PXR gene loss in Elasmobranchii (sharks and rays). Compared to other vertebrate groups, the chimaera PXR ortholog displays a diverse expression pattern (skin and gills) and a unique activation profile by classical xenobiotic ligands. Our findings provide insights into the molecular landscape of detoxification mechanisms and suggest lineage-specific adaptations in response to xenobiotics in gnathostome evolution.


Assuntos
Elasmobrânquios/classificação , Elasmobrânquios/genética , Evolução Molecular , Redes Reguladoras de Genes , Filogenia , Receptor de Pregnano X/genética , Animais , Células COS , Cercopithecus aethiops , Genes Reporter , Inativação Metabólica/genética , Luciferases/metabolismo , Receptor de Pregnano X/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Sintenia/genética , Ativação Transcricional/genética
17.
Adv Exp Med Biol ; 1135: 27-45, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31098809

RESUMO

Steroid molecules have a wide range of function in eukaryotes, including the control and maintenance of membranes, hormonal control of transcription, and intracellular signaling. X-ray crystallography has served as a successful tool for gaining understanding of the structural and mechanistic aspects of these functions by providing snapshots of steroids in complex with various types of proteins. These proteins include nuclear receptors activated by steroid hormones, several families of enzymes involved in steroid synthesis and metabolism, and proteins involved in signaling and trafficking pathways. Proteins found in some bacteria that bind and metabolize steroids have been investigated as well. A survey of the steroid-protein complexes that have been studied using crystallography and the insight learned from them is presented.


Assuntos
Hormônios/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Esteroides/metabolismo , Bactérias/metabolismo , Cristalografia por Raios X
18.
Int J Mol Sci ; 20(9)2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31035587

RESUMO

Phosphatidylinositol (PI)-related signaling plays a pivotal role in many cellular aspects, including survival, cell proliferation, differentiation, DNA damage, and trafficking. PI is the core of a network of proteins represented by kinases, phosphatases, and lipases which are able to add, remove or hydrolyze PI, leading to different phosphoinositide products. Among the seven known phosphoinositides, phosphatidylinositol 5 phosphate (PI5P) was the last to be discovered. PI5P presence in cells is very low compared to other PIs. However, much evidence collected throughout the years has described the role of this mono-phosphoinositide in cell cycles, stress response, T-cell activation, and chromatin remodeling. Interestingly, PI5P has been found in different cellular compartments, including the nucleus. Here, we will review the nuclear role of PI5P, describing how it is synthesized and regulated, and how changes in the levels of this rare phosphoinositide can lead to different nuclear outputs.


Assuntos
Núcleo Celular/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Animais , Humanos , Metabolismo dos Lipídeos , Proteínas Nucleares/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Transdução de Sinais , Estresse Fisiológico
19.
Molecules ; 24(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141879

RESUMO

We recently established a KAIMRC1 cell line that has unique features compared to the known breast cancer cell lines, MCF7 and MDA-MB231. To characterize it further, we investigated the expression profile of nuclear receptors and their respective co-factors in these cell lines. We confirm that in contrast to the triple negative cell line MDA-MB231, the MCF7 and KAIMRC1 are estrogen receptor alpha (ERa) and progesterone receptor alpha (PRa) positive, with significant lower expression of these receptors in KAIMRC1. KAIMRC1 cell is a vitamin D receptor (VDR) negative and V-ErbA-Related Protein 2 (EAR2) positive in contrast to MCF7 and MDA-MB231. Remarkably, the histone deacetylases (HDACs) are highly expressed in KAIRMC1 with HDAC6 and HDAC 7 are exclusively expressed in KAIMRC1 while thyroid hormone receptor-associated protein 80 (TRAP80), telomeric DNA binding protein 1 (TBP1) and TGF-beta receptor interacting protein (TRIP1) are absent in KAIMRC1 but present in MCF7 and MDA-MB231. In a luciferase reporter assay, the ERa coexpression is needed for estrogen receptor element (ERE)-luciferase activation by estradiol in KAIMRC1 but not in MCF7. The co-expression of exogenous Liver X receptor alpha (LXRa)/retinoid X receptor alpha (RXRa) are necessary for LXR responsive element (LXRE) activation by the GW3696 in the three cell lines. However, the activity of peroxisome proliferator-activated receptor response element (PPARE)-tk-luciferase reporter increased when peroxisome proliferator-activated receptors alpha (PPARa)/RXRa were coexpressed but the addition of PPARa agonist (GW7647) did not stimulate further the reporter. The signal of the PPARE reporter increased in a dose-dependent manner with rosiglitazone (PPARg agonist) in KAIMRC1, MCF7, and MDA-MB231 when the proliferator-activated receptors gamma (PPARg)/RXRa receptors were cotransfected. Retinoic acid-induced activation of retinoic acid receptor response element (RARE)-tk-luciferase is dependent on exogenous expression of retinoic acid receptor alpha (RARa)/RXRa heterodimer in MDA-MB 231 but not in MCF7 and KAIMRC1 cell lines. In the three cell lines, Bexarotene-induced retinoid X receptor response element (RXRE)-luciferase reporter activation was induced only if the RXRa/LXRa heterodimer were co-expressed. The vitamin D receptor response element (VDRE)-luciferase reporter activity showed another distinct feature of KAIMRC1, where only co-expression of exogenous vitamin D receptor (VDR)/RXRa heterodimer was sufficient to reach the maximum rate of activation of VDRE reporter. In the proliferation assay, nuclear receptors ligands showed a distinct effect on KAIMRC1 compared to MCF7 and MDA-MB231. Growth inhibition effects of used ligands suggest that KAIMRC1 correlate more closely to MDA-MB231 than MCF7. Vitamin D3, rosiglitazone, novel RXR compound (RXRc) and PPARa compound (GW6471) have the most profound effects. In conclusion, we showed that nuclear receptors are differentially expressed, activated and also their ligand produced distinct effects in KAIMRC1 compared to MCF7 and MDA-MB231. This finding gives us confidence that KAIMRC1 has a unique biological phenotype.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Receptores Citoplasmáticos e Nucleares/genética , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Ligantes , Receptores Citoplasmáticos e Nucleares/metabolismo , Transcrição Genética
20.
Methods Mol Biol ; 1966: 1-5, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31041734

RESUMO

In this chapter, we summarize the birth of the field of nuclear receptors. These receptors exhibit a multitude of roles in cell biology and hence have attracted a great deal of interest in the drug discovery field. It is not certain whether these receptors evolved independently or an ancestral protein acquired various functions upon binding to preexisting small molecules, ligands. Currently, members of this receptor superfamily are categorized in six groups, including "orphan receptors." Research in the area has resulted in several clinically used drugs and continues to reveal further previously unknown roles for these receptors paving the road toward more valuable discoveries in the future.


Assuntos
Receptores Nucleares Órfãos/metabolismo , Receptores de Esteroides/metabolismo , Transdução de Sinais , Animais , Humanos , Ligantes , Receptores Nucleares Órfãos/fisiologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Receptores de Esteroides/fisiologia
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