Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
1.
Eur J Med Chem ; 237: 114416, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35500473

RESUMO

Mifepristone (RU486) is a chemical contraceptive marketed in more than 55 countries and used by hundreds of millions of women worldwide. Current studies reported its uses by both genders for a safe and long-term psychotic depression and particularly for traditional cancer chemotherapy. Here, we investigated the multidisciplinary data from recent large epidemiological chemoprevention studies for long-term use of oral contraceptives to reduce cancer risk, and from the unsuccessful clinical trials of mifepristone used as a post-metastatic anticancer drug, and elucidated the similarities and differences in cellular and molecular processes between embryonic implantation to endometrium and adhesion/invasion of circulating tumor cells (CTCs) to vascular endothelium. The deep analyses provide a stronger scientific basis for repurposing abortifacients for safe and effective cancer metastatic chemoprevention. Initiation of such cancer drug development strategy represents a paradigm shift from traditional post-metastasis treatments to novel pre-metastasis chemoprevention.


Assuntos
Abortivos , Antineoplásicos , Abortivos/química , Abortivos/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Quimioprevenção , Feminino , Humanos , Masculino , Mifepristona/química , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/prevenção & controle
2.
Cancer Sci ; 113(2): 733-743, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34859546

RESUMO

Breast cancer is the leading cause of cancer death among women and almost all of the breast cancer-caused mortality is related to metastasis. It has been reported that glucocorticoid facilitates the metastasis of breast cancer in mice, and mifepristone can antagonize the effect of glucocorticoid. Paclitaxel is one of the important drugs in the treatment of breast cancer. Mifepristone combined with paclitaxel could be an effective strategy for inhibiting breast cancer metastasis. However, their inherent defects, in terms of short blood circulation half-life and lack of tumor targeting, not only limit their effectiveness but also cause adverse reactions. Therefore, our aim is to explore a novel protocol against breast cancer metastasis, further optimize its therapeutic efficacy by a nanodelivery system, and explore its mechanism. Herein, a paclitaxel-conjugated and mifepristone-loaded hydrogel (PM-nano) was prepared by self-assembly. Its characterizations were studied. The antimetastatic effect was evaluated in vitro and in vivo and its mechanism was also explored by western blot assay. The resultant PM-nano was developed with favorable water solubility and good biocompatibility. Moreover, PM-nano displayed increased cell uptake properties and stimulated drug release in the tumor micro-acidic environment. The PM-nano was more effective in inhibiting the proliferation and metastasis of breast cancer than other groups in vitro and in vivo. The PM-nano might inhibit metastasis through glucocorticoid receptor/receptor tyrosine kinase-like orphan receptor 1 and MMPs. Taken together, PM-nano showed superior antimetastatic effects against breast cancer and excellent biocompatibility in vitro and in vivo, providing a new option for limiting metastasis.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Hidrogéis/uso terapêutico , Mifepristona/uso terapêutico , Paclitaxel/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Disponibilidade Biológica , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Portadores de Fármacos/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Mifepristona/química , Mifepristona/farmacologia , Nanoestruturas/uso terapêutico , Paclitaxel/química , Paclitaxel/farmacologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Steroids ; 159: 108649, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32389717

RESUMO

Mifepristone is one of potent anti-progesterone agents, which binds to progesterone receptors and glucocorticoid receptors. Until now, there are a lot of research focusing on enhancing the solubility and oral bioavailability of Mifepristone. However, poor solubility and oral bioavailability has some undesirable consequences. In this work, Mifepristone in form D was discovered for the first time and characterized by PXRD, TGA, DSC, FT-IR, SEM and SS NMR. Form D was a metastable crystal type which manifested favorable stability under ambient conditions. Form D had better dissolution characteristic compared with commercial Mifepristone in 0.5% SDS solution. In addition, Mifepristone in form D exhibited a 1.43-fold higher peak plasma concentration (Cmax) and 1.46-fold higher area under the curve (AUC) in rats. The work in this paper is a complement to the present understanding of drug polymorphism on the in vitro and in vivo behavior, and establishes the ground work for future development of Mifepristone in form D as a promising drug for the market.


Assuntos
Antagonistas de Hormônios/química , Antagonistas de Hormônios/farmacocinética , Mifepristona/química , Mifepristona/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Feminino , Antagonistas de Hormônios/administração & dosagem , Mifepristona/administração & dosagem , Conformação Molecular , Ratos , Ratos Sprague-Dawley , Solubilidade
4.
Sci Rep ; 9(1): 2634, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30796232

RESUMO

There are currently no therapeutics to treat infection with the alphavirus Venezuelan equine encephalitis virus (VEEV), which causes flu-like symptoms leading to neurological symptoms in up to 14% of cases. Large outbreaks of VEEV can result in 10,000 s of human cases and mass equine death. We previously showed that mifepristone (RU486) has anti-VEEV activity (EC50 = 20 µM) and only limited cytotoxicity (CC50 > 100 µM), but a limitation in its use is its abortifacient activity resulting from its ability to antagonize the progesterone receptor (PR). Here we generate a suite of new mifepristone analogues with enhanced antiviral properties, succeeding in achieving >11-fold improvement in anti-VEEV activity with no detectable increase in toxicity. Importantly, we were able to derive a lead compound with an EC50 of 7.2 µM and no detectable PR antagonism activity. Finally, based on our SAR analysis we propose avenues for the further development of these analogues as safe and effective anti-VEEV agents.


Assuntos
Vírus da Encefalite Equina Venezuelana/efeitos dos fármacos , Mifepristona/análogos & derivados , Mifepristona/farmacologia , Receptores de Progesterona/antagonistas & inibidores , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Proteínas do Capsídeo/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células HeLa , Humanos , Mifepristona/síntese química , Mifepristona/química , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/metabolismo , Relação Estrutura-Atividade
5.
Steroids ; 137: 40-46, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30086355

RESUMO

During our search for bioactive secondary metabolites in the jellyfish-derived fungus Penicillium chrysogenum J08NF-4, several bile acid derivatives (2-6) were isolated along with a new steroidal artifact (1). An in vitro anti-inflammatory assay showed that pretreatment with 1 suppressed NO production and the gene expressions of the pro-inflammatory mediators iNOS and TNF-α in LPS-induced RAW 264.7 macrophages. Docking analysis of 1 revealed that it might bind to the ligand binding domain (LBD) of PPARγ in a manner similar to that of the synthetic steroid mifepristone (7), which is used clinically to treat hypercortisolism and was recently reported to be a PPARγ agonist. Compound 1 activated PPARγ in murine Ac2F liver cells and suppressed the LPS-induced phosphorylation of the NF-κB p65 subunit leading to downregulation of pro-inflammatory mediators. Our findings suggest that 1 acts as a steroidal PPARγ activator that downregulates the expressions of pro-inflammatory mediators by suppressing the NF-κB signaling pathway.


Assuntos
Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/farmacologia , PPAR gama/metabolismo , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Mifepristona/química , Mifepristona/metabolismo , Mifepristona/farmacologia , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , PPAR gama/química , Domínios Proteicos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
6.
Eur J Med Chem ; 146: 354-367, 2018 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-29407962

RESUMO

Triple-negative breast cancer (TNBC) is one of the most malignant breast cancers currently with a lack of targeted therapeutic drugs. Accumulating evidence supports that KLF5 represents a novel therapeutic target for the treatment of basal TNBC. Our previous studies revealed that mifepristone is capable of suppressing TNBC cell proliferation and promoting cancer cell apoptosis by inhibiting KLF5 expression. Nevertheless, its anticancer efficacy is only modest with high dose. Moreover, its main metabolite N-desmethyl mifepristone with the removal of one methyl moiety results in a significant loss of antiproliferative activity, indicating an important pharmacophore domain around this methyl moiety. To improve the pharmacokinetic properties including metabolic stability and enhance the anticancer activities, a focused compound library by altering this sensitive metabolic region of mifepristone has been designed and synthesized for scaffold repurposing and structural optimization. Compound 17 (FZU-00,004) has been identified with an attractive anticancer profile against TNBC via suppressing KLF5 expression.


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Mifepristona/farmacologia , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos , Camundongos Nus , Mifepristona/administração & dosagem , Mifepristona/química , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Células Tumorais Cultivadas
7.
Mol Carcinog ; 56(8): 1896-1908, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28277622

RESUMO

Recent global epidemiological studies revealed the lower ovarian cancer death from long-term use of oral contraceptives. However, the underlying mechanism of action is not clear. Here, we use the abortifacient metapristone (RU486 derivative) to test the hypothesis that the contraceptives might interrupt CXCL12/CXCR4 chemokine axis to inhibit ovarian cancer metastasis. Metapristone at concentrations (

Assuntos
Antineoplásicos/uso terapêutico , Quimiocina CXCL12/metabolismo , Mifepristona/análogos & derivados , Invasividade Neoplásica/prevenção & controle , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/prevenção & controle , Neoplasias Peritoneais/secundário , Receptores CXCR4/metabolismo , Abortivos/química , Abortivos/farmacologia , Abortivos/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Carcinoma Epitelial do Ovário , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Feminino , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mifepristona/química , Mifepristona/farmacologia , Mifepristona/uso terapêutico , Invasividade Neoplásica/patologia , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/patologia , Peritônio/efeitos dos fármacos , Peritônio/metabolismo , Peritônio/patologia , Transdução de Sinais/efeitos dos fármacos
8.
Arch Biochem Biophys ; 603: 102-9, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27246478

RESUMO

Glucocorticoids (GCs) are a class of steroid hormones that regulate multiple aspects of glucose homeostasis. In skeletal muscle, it is well established that prolonged GC excess inhibits glucose uptake and utilization through glucocorticoid receptor (GR)-mediated transcriptional changes. However, it remains obscure that whether the rapid non-genomic effects of GC on glucose uptake are involved in acute exercise stress. Therefore, we used electric pulse stimulation (EPS)-evoked contracting myotubes to determine whether the non-genomic actions of GC were involved and its underlying mechanism(s). Pretreatment with dexamethasone (Dex, 10 µM) significantly prevented contraction-stimulated glucose uptake and glucose transporter 4 (Glut4) translocation within 20 min in C2C12 myotubes. Neither GC nuclear receptor antagonist (RU486) nor protein synthesis inhibitor (cycloheximide, Chx) affected the rapid inhibition effects of Dex. AMPK and CaMKII-dependent signaling pathways were associated with the non-genomic effects of Dex. These results provide evidence that GC rapidly suppresses glucose uptake in contracting myotubes via GR-independent non-genomic mechanisms. AMPK and CaMKII-mediated Glut4 translocation may play a critical role in GC-induced rapid inhibition of glucose uptake.


Assuntos
Dexametasona/química , Glucose/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Anti-Inflamatórios/química , Cálcio/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Diferenciação Celular , Linhagem Celular , Membrana Celular/metabolismo , Cicloeximida/química , Genômica , Transportador de Glucose Tipo 4/metabolismo , Camundongos , Mifepristona/química , Músculo Esquelético/metabolismo , Fosforilação , Condicionamento Físico Animal , Transporte Proteico , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais , Esteroides/química , Transcrição Gênica
9.
Small ; 12(19): 2595-608, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27027489

RESUMO

The circulating tumor cells (CTCs) existing in cancer survivors are considered the root cause of cancer metastasis. To prevent the devastating metastasis cascade from initiation, we hypothesize that a biodegradable nanomaterial loaded with the abortifacient mifepristone (MIF) and conjugated with the epithelial cell adhesion molecule antibody (aEpCAM) may serve as a safe and effective cancer metastatic preventive agent by targeting CTCs and preventing their adhesion-invasion to vascular intima. It is demonstrated that MIF-loaded mesoporous silica nanoparticles (MSN) coated with aEpCAM (aE-MSN-M) can specifically target and bind colorectal cancer cells in either cell medium or blood through EpCAM recognition proven by quantitative flow cytometric detection and free aEpCAM competitive assay. The specific binding results in downregulation of the captured cells and drives them into G0/G1 phase primarily attributed to the effect of aEpCAM. The functional nanoparticles significantly inhibit the heteroadhesion between cancer cells and endothelial cells, suggesting the combined inhibition effects of aEpCAM and MIF on E-selectin and ICAM-1 expression. The functionalized nanoparticles circulate in mouse blood long enough to deliver MIF and inhibit lung metastasis. The present proof-of-concept study shows that the aE-MSN-M can prevent cancer metastasis by restraining CTC activity and their adhesion-invasion to vascular intima.


Assuntos
Anticorpos Monoclonais/imunologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/secundário , Molécula de Adesão da Célula Epitelial/imunologia , Mifepristona/administração & dosagem , Nanocápsulas/química , Dióxido de Silício/química , Abortivos Esteroides/administração & dosagem , Abortivos Esteroides/química , Absorção Fisico-Química , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/imunologia , Difusão , Sistemas de Liberação de Medicamentos/métodos , Reposicionamento de Medicamentos , Células HT29 , Humanos , Camundongos , Mifepristona/química , Nanocápsulas/ultraestrutura , Nanoconjugados/administração & dosagem , Nanoconjugados/química , Nanoporos/ultraestrutura , Resultado do Tratamento
10.
Biochem Biophys Res Commun ; 473(1): 29-34, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26993165

RESUMO

Previous studies indicated that maturation inducing hormone, 17α, 20ß-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120 dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90 dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish.


Assuntos
Ciclídeos/fisiologia , Ovário/citologia , Progestinas/fisiologia , Receptores de Progesterona/antagonistas & inibidores , Animais , Diferenciação Celular , Estrogênios/química , Feminino , Perfilação da Expressão Gênica , Hidroxiprogesteronas/química , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Masculino , Meiose , Mifepristona/química , Mitose , Reação em Cadeia da Polimerase , Diferenciação Sexual , Espermatogênese
11.
J Reprod Dev ; 61(1): 67-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25451535

RESUMO

The corpus luteum (CL) forms after ovulation and acts as a temporary endocrine gland that produces progesterone (P4), a hormone that is essential for implantation and maintenance of pregnancy in mammals. In pregnant women, human chorionic gonadotropin (hCG) secreted by the conceptus prevents luteolysis. hCG also increases the survival of cultured human luteinized granulosa cells (hLGCs). To clarify the maintenance mechanism of the human CL, we investigated the effects of hCG and P4 receptor antagonists, onapristone (OP) and RU486, on the viability of hLGCs. With the patients' consent, hLGCs were isolated from follicular aspirates for in vitro fertilization. The cells were cultured with hCG (0.1, 1, 10, 100 IU/ml), OP (10, 25, 50, 100 µM), RU486 (100 µM), P4 (1, 10, 25, 50 µM) or some combination of the four for 24 h. Cell viability was significantly increased by hCG (100 IU/ml) and significantly decreased by OP (100 µM) compared with the control. Cells treated with hCG and OP together were significantly less viable than the control and OP-treated cells. The combined treatment also significantly increased CASP3 activity and cleaved CASP3 protein expression. Furthermore, P4 addition reversed the reduction in cell viability caused by the combination of hCG and OP treatment. The overall findings suggest that hCG cooperates with P4 to increase survival of hLGCs and to induce apoptosis when P4 action supported by hCG is attenuated in the human CL.


Assuntos
Apoptose , Gonadotropina Coriônica/metabolismo , Células da Granulosa/efeitos dos fármacos , Hormônio Luteinizante/metabolismo , Adulto , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Fertilização in vitro , Gonanos/química , Células da Granulosa/citologia , Humanos , Técnicas Imunoenzimáticas , Luteólise , Mifepristona/química , Progesterona/metabolismo
12.
Steroids ; 92: 45-55, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25174783

RESUMO

Antiprogestins with a 4' para imidazolylphenyl moiety were synthesized and their biochemical interactions with the progesterone and glucocorticoid receptor were investigated. Depending on the substitution pattern at the 17 position partial progesterone receptor (PR)-agonistic derivatives like compounds EC339 and EC336 or pure antagonists like compound EC317 were obtained. EC317 was investigated in vivo and found to be significantly more potent than RU 486 in cycling and pregnant guinea pigs. For testing the biological action progesterone receptor modulators (PRM), guinea pigs appears as a specific model when compare to pregnant human uterus. This model correlates to human conditions such as softening and widening of the cervix, the elevation of the uterine responsiveness to prostaglandins and oxytocin, and finally to induction of labor. The use of non-pregnant guinea pigs permitted the simultaneous assessment of PR-agonistic and PR-antagonistic properties and their physiological interactions with uterine and vaginal environment. These can histologically be presumed from the presence of estrogen or progesterone dominance in the genital tract tissues. The ovarian histology indicated the effects on ovulation. Corpora lutea in guinea pigs further reflects inhibitory effects of the progesterone-dependent uterine prostaglandin secretion. PRMs are initially synthesized as analogues of RU 486. They represent a heterogeneous group of compounds with different ratios of PR-agonistic and-antagonistic properties. PR-agonistic properties may be essential for uterine anti-proliferative effects. In various clinical studies these were also attributed to RU 486 or Ulipristal [1,2]. Adjusted PR-agonistic PRMs (EC312, EC313) [3] may be more effective in achieving a mitotically resting endometrium and superior uterine tumor inhibition. For the use in termination of pregnancy, progesterone-inhibitory effects are essentially needed. Even minor PR-agonistic properties compromise the therapeutic goals. Pure PR-antagonists, as EC317, clearly exceeded the gold standard RU 486 with respect to labor inducing effects. Mechanistically it is surprising that both types of compound may be potent inhibitors of ovulation.


Assuntos
Antagonistas de Hormônios/síntese química , Animais , Linhagem Celular , Feminino , Cobaias , Antagonistas de Hormônios/química , Antagonistas de Hormônios/farmacologia , Humanos , Mifepristona/química , Mifepristona/farmacologia , Modelos Moleculares , Gravidez , Progesterona/antagonistas & inibidores , Progestinas/antagonistas & inibidores , Útero/efeitos dos fármacos
13.
J Biol Chem ; 289(42): 29235-46, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25164807

RESUMO

Leigh Syndrome (LS) is the most common early-onset, progressive mitochondrial encephalopathy usually leading to early death. The single most prevalent cause of LS is occurrence of mutations in the SURF1 gene, and LS(Surf1) patients show a ubiquitous and specific decrease in the activity of mitochondrial respiratory chain complex IV (cytochrome c oxidase, COX). SURF1 encodes an inner membrane mitochondrial protein involved in COX assembly. We established a Drosophila melanogaster model of LS based on the post-transcriptional silencing of CG9943, the Drosophila homolog of SURF1. Knockdown of Surf1 was induced ubiquitously in larvae and adults, which led to lethality; in the mesodermal derivatives, which led to pupal lethality; or in the central nervous system, which allowed survival. A biochemical characterization was carried out in knockdown individuals, which revealed that larvae unexpectedly displayed defects in all complexes of the mitochondrial respiratory chain and in the F-ATP synthase, while adults had a COX-selective impairment. Silencing of Surf1 expression in Drosophila S2R(+) cells led to selective loss of COX activity associated with decreased oxygen consumption and respiratory reserve. We conclude that Surf1 is essential for COX activity and mitochondrial function in D. melanogaster, thus providing a new tool that may help clarify the pathogenic mechanisms of LS.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Doença de Leigh/genética , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Complexos de ATP Sintetase/metabolismo , Animais , Linhagem Celular , Proteínas de Drosophila/fisiologia , Transporte de Elétrons , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Perfilação da Expressão Gênica , Inativação Gênica , Humanos , Potencial da Membrana Mitocondrial , Proteínas de Membrana/fisiologia , Mifepristona/química , Mitocôndrias/enzimologia , Proteínas Mitocondriais/fisiologia , Mutação , Oxigênio/metabolismo , Interferência de RNA , Processamento Pós-Transcricional do RNA , RNA de Cadeia Dupla/química , Transcrição Gênica
14.
Structure ; 22(7): 961-73, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24909783

RESUMO

Structural and functional details of the N-terminal activation function 1 (AF1) of most nuclear receptors are poorly understood due to the highly dynamic intrinsically disordered nature of this domain. A hydrogen/deuterium exchange (HDX) mass-spectrometry-based investigation of TATA box-binding protein (TBP) interaction with various domains of progesterone receptor (PR) demonstrate that agonist-bound PR interaction with TBP via AF1 impacts the mobility of the C-terminal AF2. Results from HDX and other biophysical studies involving agonist- and antagonist-bound full-length PR and isolated PR domains reveal the molecular mechanism underlying synergistic transcriptional activation mediated by AF1 and AF2, dominance of PR-B isoform over PR-A, and the necessity of AF2 for full AF1-mediated transcriptional activity. These results provide a comprehensive picture elaborating the underlying mechanism of PR-TBP interactions as a model for studying nuclear receptor (NR)-transcription factor functional interactions.


Assuntos
Espectrometria de Massas/métodos , Conformação Proteica , Estrutura Terciária de Proteína , Receptores de Progesterona/química , Sequência de Aminoácidos , Animais , Medição da Troca de Deutério , Humanos , Ligantes , Mifepristona/química , Mifepristona/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Promegestona/química , Promegestona/metabolismo , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Células Sf9 , Proteína de Ligação a TATA-Box/química , Proteína de Ligação a TATA-Box/metabolismo
15.
Proc Natl Acad Sci U S A ; 111(20): 7462-7, 2014 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-24808139

RESUMO

Studies of stress effects on the brain have traditionally focused on neurons, without considering the cerebral microcirculation. Here we report that stress impairs neurovascular coupling (NVC), the process that matches neuronal activity with increased local blood flow. A stressed phenotype was induced in male rats by administering a 7-d heterotypical stress paradigm. NVC was modeled by measuring parenchymal arteriole (PA) vasodilation in response to neuronal stimulation in amygdala brain slices. After stress, vasodilation of PAs to neuronal stimulation was greatly reduced, and dilation of isolated PAs to external K(+) was diminished, suggesting a defect in smooth muscle inwardly rectifying K(+) (KIR) channel function. Consistent with these observations, stress caused a reduction in PA KIR2.1 mRNA and smooth muscle KIR current density, and blocking KIR channels significantly inhibited NVC in control, but not in stressed, slices. Delivery of corticosterone for 7 d (without stressors) or RU486 (before stressors) mimicked and abrogated NVC impairment by stress, respectively. We conclude that stress causes a glucocorticoid-mediated decrease in functional KIR channels in amygdala PA myocytes. This renders arterioles less responsive to K(+) released from astrocytic endfeet during NVC, leading to impairment of this process. Because the fidelity of NVC is essential for neuronal health, the impairment characterized here may contribute to the pathophysiology of brain disorders with a stress component.


Assuntos
Glucocorticoides/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Transdução de Sinais , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Arteríolas/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Corticosterona/química , Glucose/metabolismo , Antagonistas de Hormônios/química , Sistema Límbico/efeitos dos fármacos , Masculino , Mifepristona/química , Neurônios/fisiologia , Oxigênio/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley , Estresse Psicológico , Fatores de Tempo , Vasodilatação/efeitos dos fármacos
16.
AAPS J ; 16(2): 289-98, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24442753

RESUMO

Mifepristone (RU486) is marketed and used widely by women as an abortifacient, and experimentally for psychotic depression and anticancer treatments. After administration, metapristone is found to be the most predominant metabolite of mifepristone. We hypothesized that adhesion of circulating tumor cells (CTCs) to vascular endothelial bed is a crucial starting point in metastatic cascade, and that metapristone can serve as a cancer metastatic chemopreventive agent that can interrupt adhesion and invasion of CTCs to the intima of microvasculature. In the present study, we modified the synthesis procedure to produce grams of metapristone, fully characterized its spectral properties and in vitro cellular activities, including its cytostatic effects, cell cycle arrest, mitochondrial membrane potential, and apoptosis on human colorectal cancer HT-29 cells. Metapristone concentration dependently interrupted adhesion of HT-29 cells to endothelial cells. Metapristone may potentially be a useful agent to interrupt metastatic initiation.


Assuntos
Anticarcinógenos/síntese química , Mifepristona/análogos & derivados , Mifepristona/química , Metástase Neoplásica/prevenção & controle , Anexina A5/metabolismo , Anticarcinógenos/química , Anticarcinógenos/farmacologia , Caspase 3/metabolismo , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatografia Líquida , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mifepristona/síntese química , Mifepristona/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Pharmacol Exp Ther ; 348(1): 192-201, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24163440

RESUMO

Weight gain and diabetes have been reported during treatment with atypical antipsychotic drugs (AAPDs). Patients treated with the glucocorticoid receptor antagonist (GRA) and the progesterone receptor antagonist (PRA) mifepristone [estra-4,9-dien-3-one, 11-[4-(dimethylamino)phenyl]-17-hydroxy-17-(1-propynyl)-(11ß,17ß)-(9CI)] experienced significant reduction in the weight gain observed when patients were treated with olanzapine or risperidone. To understand the pharmacology responsible for this finding, we discovered LLY-2707 [N-(5-(tert-butyl)-3-(2-fluoro-5-methylpyridin-4-yl)-2-methyl-1H-indol-7-yl)methanesulfonamide], a novel and selective GRA, and evaluated its utility in preclinical models of AAPD-associated weight gain and diabetes. In vitro, LLY-2707 was a highly selective and potent GRA. GR occupancy in vivo was assessed using ex vivo binding where LLY-2707 inhibited [(3)H]dexamethasone binding to the liver. Modest but statistically significant decreases in brain ex vivo binding were observed with high doses of CORT-108297 [(R)-4α-(ethoxymethyl)-1-(4-fluorophenyl)-6-((4-(trifluoromethyl)phenyl)sulfonyl)-4,4a,5,6,7,8-hexahydro-1H-pyrazolo[3,4-g]isoquinoline] and LLY-2707, but mifepristone inhibited at all doses. Central activity of the GRAs was confirmed by their ability to suppress amphetamine-induced increases in locomotor activity. The increases in the body weight of female rats treated with olanzapine (2 mg/kg PO) over 14 days were reduced in a dose-dependent manner by coadministration of LLY-2707. Similar decreases, although less robust, in body weight were seen with mifepristone and CORT-108297. In addition, sGRAs prevented the glucose excursion after intragastric olanzapine infusions consistent with a direct effect on the hyperglycemia observed during treatment with AAPDs. At doses effectively preventing weight gain, LLY-2707 did not substantially interfere with the dopamine D2 receptor occupancy by olanzapine. Therefore, GRA coadministration may provide a novel treatment modality to prevent the weight gain and diabetes observed during treatment with AAPDs.


Assuntos
Antipsicóticos/toxicidade , Indóis/farmacologia , Receptores de Glucocorticoides/antagonistas & inibidores , Sulfonamidas/farmacologia , Aumento de Peso/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos , Animais , Compostos Aza/química , Compostos Aza/farmacologia , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Feminino , Células HEK293 , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Indóis/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mifepristona/química , Mifepristona/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/fisiologia , Sulfonamidas/química , Aumento de Peso/fisiologia , Redução de Peso/fisiologia
18.
PLoS One ; 8(11): e80761, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24260475

RESUMO

Steroid receptors are a subfamily of nuclear receptors found throughout all metazoans. They are highly important in the regulation of development, inflammation, and reproduction and their misregulation has been implicated in hormone insensitivity syndromes and cancer. Steroid binding to SRs drives a conformational change in the ligand binding domain that promotes nuclear localization and subsequent interaction with coregulator proteins to affect gene regulation. SRs are important pharmaceutical targets, yet most SR-targeting drugs have off-target pharmacology leading to unwanted side effects. A better understanding of the structural mechanisms dictating ligand specificity and the evolution of the forces that created the SR-hormone pairs will enable the design of better pharmaceutical ligands. In order to investigate this relationship, we attempted to crystallize the ancestral 3-ketosteroid receptor (ancSR2) with mifepristone, a SR antagonist. Here, we present the x-ray crystal structure of the ancestral 3-keto steroid receptor (ancSR2)-progesterone complex at a resolution of 2.05 Å. This improves upon our previously reported structure of the ancSR2-progesterone complex, permitting unambiguous assignment of the ligand conformation within the binding pocket. Surprisingly, we find mifepristone, fortuitously docked at the protein surface, poised to interfere with coregulator binding. Recent attention has been given to generating pharmaceuticals that block the coregulator binding site in order to obstruct coregulator binding and achieve tissue-specific SR regulation independent of hormone binding. Mifepristone's interaction with the coactivator cleft of this SR suggests that it may be a useful molecular scaffold for further coactivator binding inhibitor development.


Assuntos
Mifepristona/química , Complexos Multiproteicos/química , Progesterona/química , Receptores de Esteroides/química , Sequência de Aminoácidos , Sítios de Ligação , Cristalização , Cristalografia por Raios X , Humanos , Mifepristona/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Progesterona/metabolismo , Ligação Proteica , Conformação Proteica , Receptores de Esteroides/metabolismo , Alinhamento de Sequência
19.
Steroids ; 78(2): 255-67, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23178161

RESUMO

A series of antiprogestins have been synthesized by partially fluorinating the steroid molecule in positions relevant for receptor binding. By introducing fluorine at the exo-methylene of the 17 spirofuran ring, we obtained partial agonists (mesoprogestins) with significant applications for antiproliferative and antiovulatory treatment strategies in gynecological therapy such as uterine fibroids, endometriosis and heavy menstrual bleeding. Compared to the standard drug RU486, our synthesized compounds exhibited considerable dissociation between antiprogestational and antiglucocorticoid PR receptors. Furthermore, our studies have shown that pure antiprogestins can be generated by partially fluorinating the 17 propenyl and propynl group or by substituting the 4' acetyl phenyl group in the 11 position using trifluromethyl group.


Assuntos
Halogenação/efeitos dos fármacos , Antagonistas de Hormônios/síntese química , Antagonistas de Hormônios/farmacologia , Progestinas/síntese química , Progestinas/farmacologia , Animais , Feminino , Cobaias , Células HEK293 , Humanos , Espectroscopia de Ressonância Magnética , Mifepristona/análogos & derivados , Mifepristona/química , Mifepristona/farmacologia , Progestinas/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/antagonistas & inibidores , Receptores de Progesterona/metabolismo , Vagina/citologia , Vagina/efeitos dos fármacos
20.
Curr Pharm Biotechnol ; 13(15): 2761-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23072393

RESUMO

The progression of Alzheimer's disease (AD) is accompanied by disturbances of the endosome/lysosome (EL) system and there is accumulation of peptides of the AD-associated amyloid beta (Abeta) type in EL vesicles of affected neurons. EL modulating agents partially ameliorate the Abeta-mediated cell abnormalities. However, no extensive studies on the potential pharmaceutical applications of combinations of such agents and their synergistic effects have been performed. This study shows the beneficial anti-amyloid effects of several combinations of lysosomal modulators and other pharmacological and new nanobiotechnological agents. Some agents potentiated each other's action and some of them facilitated the anti-amyloid actions of memantine, a modifier of Ca2+-permeable channels involved in AD and one of the few drugs used for treatment of AD. Another compound used in nanobiotechnology ameliorated as a nanocarrier the beneficial effects of some of these potential pharmaceutical agents. They may be considered as additional drugs to improve the efficacy of the therapeutic approaches for AD and related neurodegenerative disorders.


Assuntos
Peptídeos beta-Amiloides , Lisossomos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Acetilcarnitina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Endossomos/efeitos dos fármacos , Humanos , Quempferóis/farmacologia , Ácido Láctico/química , Memantina/farmacologia , Mifepristona/química , Nanopartículas/administração & dosagem , Nanopartículas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Resveratrol , Estilbenos/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...