RESUMO
Coronavirus disease 2019 (COVID-19) is a newly emerged infectious disease caused by a novel coronavirus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The rapid global emergence of SARS-CoV-2 highlights the importance and urgency for potential drugs to control the pandemic. The functional importance of RNA-dependent RNA polymerase (RdRp) in the viral life cycle, combined with structural conservation and absence of closely related homologs in humans, makes it an attractive target for designing antiviral drugs. Nucleos(t)ide analogs (NAs) are still the most promising broad-spectrum class of viral RdRp inhibitors. In this study, using our previously developed cell-based SARS-CoV-2 RdRp report system, we screened 134 compounds in the Selleckchemicals NAs library. Four candidate compounds, Fludarabine Phosphate, Fludarabine, 6-Thio-20-Deoxyguanosine (6-Thio-dG), and 5-Iodotubercidin, exhibit remarkable potency in inhibiting SARS-CoV-2 RdRp. Among these four compounds, 5-Iodotubercidin exhibited the strongest inhibition upon SARS-CoV-2 RdRp, and was resistant to viral exoribonuclease activity, thus presenting the best antiviral activity against coronavirus from a different genus. Further study showed that the RdRp inhibitory activity of 5-Iodotubercidin is closely related to its capacity to inhibit adenosine kinase (ADK).
Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Inibidores da Síntese de Ácido Nucleico/farmacologia , SARS-CoV-2/efeitos dos fármacos , Tubercidina/análogos & derivados , Linhagem Celular , Desoxiguanosina/análogos & derivados , Desoxiguanosina/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , RNA Viral/biossíntese , RNA Polimerase Dependente de RNA/antagonistas & inibidores , SARS-CoV-2/genética , Tionucleosídeos/farmacologia , Tubercidina/farmacologia , Vidarabina/análogos & derivados , Vidarabina/farmacologia , Fosfato de Vidarabina/análogos & derivados , Fosfato de Vidarabina/farmacologiaRESUMO
Herpes simplex viruses-1 and -2 (HSV-1 and -2) are two of the three human alphaherpesviruses that cause infections worldwide. Since both viruses can be acquired in the absence of visible signs and symptoms, yet still result in lifelong infection, it is imperative that we provide interventions to keep them at bay, especially in immunocompromised patients. While numerous experimental vaccines are under consideration, current intervention consists solely of antiviral chemotherapeutic agents. This review explores all of the clinically approved drugs used to prevent the worst sequelae of recurrent outbreaks by these viruses.
Assuntos
Antivirais/uso terapêutico , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Antivirais/efeitos adversos , Antivirais/farmacocinética , Antivirais/farmacologia , Disponibilidade Biológica , DNA Polimerase Dirigida por DNA/metabolismo , Farmacorresistência Viral , Herpes Simples/virologia , Humanos , Inibidores da Síntese de Ácido Nucleico/efeitos adversos , Inibidores da Síntese de Ácido Nucleico/farmacocinética , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Ligação Viral/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacosRESUMO
With CA16, enterovirus-71 is the causative agent of hand foot and mouth disease (HFMD) which occurs mostly in children under 5 years-old and responsible of several outbreaks since a decade. Most of the time, HFMD is a mild disease but can progress to severe complications such as meningitis, brain stem encephalitis, acute flaccid paralysis (AFP) and even death; EV71 has been identified in all severe cases. Therefore, it is actually one of the most public health issues that threatens children's life. [Formula: see text] is a protease which plays important functions in EV71 infection. To date, a lot of [Formula: see text] inhibitors have been tested but none of them has been approved yet. Therefore, a drug screening is still an utmost importance in order to treat and/or prevent EV71 infections. This work highlights the EV71 life cycle, [Formula: see text] functions and [Formula: see text] inhibitors recently screened. It permits to well understand all mechanisms about [Formula: see text] and consequently allow further development of drugs targeting [Formula: see text]. Thus, this review is helpful for screening of more new [Formula: see text] inhibitors or for designing analogues of well known [Formula: see text] inhibitors in order to improve its antiviral activity.
Assuntos
Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Enterovirus Humano A/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Doença de Mão, Pé e Boca/tratamento farmacológico , RNA Viral/antagonistas & inibidores , Animais , Antivirais/isolamento & purificação , Criança , Avaliação Pré-Clínica de Medicamentos/tendências , Enterovirus Humano A/enzimologia , Inibidores Enzimáticos/isolamento & purificação , Doença de Mão, Pé e Boca/complicações , Doença de Mão, Pé e Boca/virologia , Humanos , Camundongos , Inibidores da Síntese de Ácido Nucleico/farmacologia , FilogeniaRESUMO
Hepatitis B virus (HBV) polymerase seems to be very hard to express and purify sufficiently, which has long hampered the generation of anti-HBV drugs based on the nature of the polymerase. To date, there has been no useful system developed for drug screening against HBV polymerase. In this study, we successfully obtained a highly purified reverse transcriptase (RT) domain of the polymerase, which has a template/primer and substrate binding activity, and established a novel high-throughput screening (HTS) system using purified RT protein for finding novel polymerase inhibitors. To examine whether the assay system provides reliable results, we tested the small scale screening using pharmacologically active compounds. As a result, the pilot screening identified already-known anti-viral polymerase agents. Then, we screened 20,000 chemical compounds and newly identified four hits. Several of these compounds inhibited not only the HBV RT substrate and/ template/primer binding activity, but also Moloney murine leukemia virus RT activity, which has an elongation activity. Finally, these candidates did show to be effective even in the cell-based assay. Our screening system provides a useful tool for searching candidate inhibitors against HBV.
Assuntos
Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Produtos do Gene pol/antagonistas & inibidores , Vírus da Hepatite B/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Células Hep G2 , Vírus da Hepatite B/enzimologia , Ensaios de Triagem em Larga Escala , Humanos , Inibidores da Síntese de Ácido Nucleico/farmacologia , DNA Polimerase Dirigida por RNA , Bibliotecas de Moléculas Pequenas , Replicação Viral/efeitos dos fármacosRESUMO
Mammarenaviruses cause chronic infections in rodents, which are their predominant natural hosts. Human infection with some of these viruses causes high-consequence disease, posing significant issues in public health. Currently, no FDA-licensed mammarenavirus vaccines are available, and anti-mammarenavirus drugs are limited to an off-label use of ribavirin, which is only partially efficacious and associated with severe side effects. Dihydroorotate dehydrogenase (DHODH) inhibitors, which block de novo pyrimidine biosynthesis, have antiviral activity against viruses from different families, including Arenaviridae, the taxonomic home of mammarenaviruses. Here, we evaluate five novel DHODH inhibitors for their antiviral activity against mammarenaviruses. All tested DHODH inhibitors were potently active against lymphocytic choriomeningitis virus (LCMV) (half-maximal effective concentrations [EC50] in the low nanomolar range, selectivity index [SI] > 1000). The tested DHODH inhibitors did not affect virion cell entry or budding, but rather interfered with viral RNA synthesis. This interference resulted in a potent interferon-independent inhibition of mammarenavirus multiplication in vitro, including the highly virulent Lassa and Junín viruses.
Assuntos
Antivirais/farmacologia , Arenaviridae/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Animais , Arenaviridae/classificação , Arenaviridae/fisiologia , Chlorocebus aethiops , Di-Hidro-Orotato Desidrogenase , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Células HEK293 , Humanos , Interferons , Camundongos , Camundongos Endogâmicos C57BL , Inibidores da Síntese de Ácido Nucleico/química , Inibidores da Síntese de Ácido Nucleico/farmacologia , Pirimidinas/biossíntese , Células Vero , Replicação Viral/efeitos dos fármacosRESUMO
Since the end of 2019, a new type of coronavirus pneumonia (COVID-19) caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been spreading rapidly throughout the world. Previously, there were two outbreaks of severe coronavirus caused by different coronaviruses worldwide, namely Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This article introduced the origin, virological characteristics and epidemiological overview of SARS-CoV-2, reviewed the currently known drugs that may prevent and treat coronavirus, explained the characteristics of the new coronavirus and provided novel information for the prevention and treatment of COVID-19.
Assuntos
Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Amidas/farmacologia , Amidas/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , COVID-19 , Cloroquina/análogos & derivados , Cloroquina/uso terapêutico , Clorpromazina/uso terapêutico , Coronavirus/genética , Infecções por Coronavirus/genética , Ciclofilinas/antagonistas & inibidores , Desenvolvimento de Medicamentos , Reposicionamento de Medicamentos , Medicamentos de Ervas Chinesas/uso terapêutico , Endocitose/efeitos dos fármacos , Humanos , Soros Imunes , Indutores de Interferon/uso terapêutico , Inibidores da Síntese de Ácido Nucleico/farmacologia , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Pneumonia Viral/genética , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Resveratrol/farmacologia , Resveratrol/uso terapêutico , SARS-CoV-2 , Vacinas Virais/uso terapêutico , Tratamento Farmacológico da COVID-19RESUMO
OBJECTIVE: The rise in primary and revision surgeries utilizing joint replacement implants suggest the need for more reliable means of promoting implant fixation. Zoledronate-(Zol), cytochalasin-D-(cytoD), and desferrioxamine-(DFO) have been shown to enhance mesenchymal stem cell (MSC) differentiation into osteoblasts promoting bone formation. The objective was to determine whether Zol, cytoD, and DFO can improve fixation strength and enhance peri-implant bone volume about intra-medullary femoral implants. METHODS: 48 Sprague-Dawley female rats were randomized into four treatments, saline-control or experimental: Zol-(0.8 µg/µL), cytoD-(0.05 µg/µL), DFO-(0.4 µg/µL). Implants were placed bilaterally in the femoral canals following injection of treatment solution and followed for 28 days. Mechanical push-out testing and micro-CT were our primary evaluations, measuring load to failure and bone volume. Qualitative evaluation included histological assessment. Data was analyzed with a one-way ANOVA with Holm-Sidak mean comparison testing. RESULTS: Significant results included pushout tests showing an increase in maximum energy for Zol (124%) and cytoD (82%); Zol showed an increase in maximum load by 48%; Zol micro-CT showed increase in BV/TV by 35%. CONCLUSIONS: Our findings suggest that locally applied Zol and cytoD enhance implant mechanical stability. Bisphosphonates and actin regulators, like cytoD, might be further investigated as a new strategy for improving osseointegration.
Assuntos
Conservadores da Densidade Óssea/farmacologia , Prótese Ancorada no Osso , Citocalasina D/farmacologia , Desferroxamina/farmacologia , Fêmur/diagnóstico por imagem , Ácido Zoledrônico/farmacologia , Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Fêmur/efeitos dos fármacos , Fêmur/cirurgia , Modelos Animais , Inibidores da Síntese de Ácido Nucleico/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sideróforos/farmacologiaRESUMO
The limited therapeutic options and increasing drug-resistance call for next-generation influenza antivirals. Due to the essential function in viral replication and high sequence conservation among influenza viruses, influenza polymerase PA-PB1 protein-protein interaction becomes an attractive drug target. Here, we developed an in vitro split luciferase complementation-based assay to speed up screening of PA-PB1 interaction inhibitors. By screening 10,000 compounds, we identified two PA-PB1 interaction inhibitors, R160792 and R151785, with potent and broad-spectrum antiviral activity against a panel of influenza A and B viruses, including amantadine-, oseltamivir-, or dual resistant strains. Further mechanistic study reveals that R151785 inhibits PA nuclear localization, reduces the levels of viral RNAs and proteins, and inhibits viral replication at the intermediate stage, all of which are in line with its antiviral mechanism of action. Overall, we developed a robust high throughput-screening assay for screening broad-spectrum influenza antivirals targeting PA-PB1 interaction and identified R151785 as a promising antiviral drug candidate.
Assuntos
Antivirais/química , RNA Polimerases Dirigidas por DNA/química , Luciferases/química , Inibidores da Síntese de Ácido Nucleico/química , Orthomyxoviridae/enzimologia , Proteínas Virais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ensaios de Triagem em Larga Escala , Humanos , Técnicas In Vitro , Simulação de Acoplamento Molecular , Estrutura Molecular , Inibidores da Síntese de Ácido Nucleico/farmacologia , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
Emerging widespread bacterial resistance to current antibiotics with traditional targets is one of the major global concerns. Therefore, so many investigations are exploring the potential of other druggable macromolecules of bacteria such as replication machinery components that are not addressed by previous antibiotics. DNA polymerase is the major part of this machine. However, a few studies have been done on it so far. In this respect, we report the discovery of four new plant-based leads against DNA polymerase (pol) IIIC (three leads) and pol IIIE (one lead) of Gram-positive and negative bacteria by combining a sequentially constrained high-throughput virtual screenings on Traditional Chinese Medicine Database with in vitro assays. The compounds displayed relatively good levels of inhibitory effect. They were active against their designated targets at micromolar concentrations. The IC50 values for them are ranged from 25 to 111 µM. In addition, they showed minimum inhibitory concentrations in the range of 8-128 µg/mL against five representatives of pathogenic bacteria species. However, they were inactive against Pseudomonas aeruginosa. Given these results, these leads hold promise for future modification and optimization to be more effective in lower concentrations and also against most of the important bacterial species. Communicated by Ramaswamy H. Sarma.
Assuntos
DNA Polimerase III/química , Replicação do DNA/efeitos dos fármacos , Chumbo/farmacologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Antibacterianos/efeitos adversos , Simulação por Computador , DNA Polimerase III/antagonistas & inibidores , Farmacorresistência Bacteriana/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Humanos , Chumbo/química , Testes de Sensibilidade Microbiana , Inibidores da Síntese de Ácido Nucleico/química , Células Procarióticas/efeitos dos fármacos , Células Procarióticas/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidadeRESUMO
Dengue is a mosquito-borne disease of global public health importance caused by four genetically and serologically related viruses (DENV-1 to DENV-4). Efforts to develop effective vaccines and therapeutics for dengue have been slowed by the paucity of preclinical models that mimic human disease. DENV-2 models in interferon receptor deficient AG129 mice were an important advance but only allowed testing against a single DENV serotype. We have developed complementary AG129 mouse models of severe disseminated dengue infection using strains of the other three DENV serotypes. Here we used the adenosine nucleoside inhibitor NITD-008 to show that these models provide the ability to perform comparative preclinical efficacy testing of candidate antivirals in vivo against the full-spectrum of DENV serotypes. Although NITD-008 was effective in modulating disease caused by all DENV serotypes, the variability in protection among DENV serotypes was greater than expected from differences in activity in in vitro testing studies emphasizing the need to undertake spectrum of activity testing to help in prioritization of candidate compounds for further development.
Assuntos
Antivirais/uso terapêutico , Vírus da Dengue/efeitos dos fármacos , Modelos Animais de Doenças , Inibidores da Síntese de Ácido Nucleico/uso terapêutico , Dengue Grave/tratamento farmacológico , Adenosina/química , Animais , Avaliação Pré-Clínica de Medicamentos , Camundongos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Estudo de Prova de Conceito , SorogrupoRESUMO
Background: Glioblastoma (GBM) is the most common and most aggressive primary malignant brain tumor. Standard-of-care treatment involves maximal surgical resection of the tumor followed by radiation and chemotherapy (temozolomide [TMZ]). The 5-year survival rate of patients with GBM is <10%, a colossal failure that has been partially attributed to intrinsic and/or acquired resistance to TMZ through O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status in the tumor. Methods: A drug screening aimed at evaluating the potential recycling and repurposing of known drugs was conducted in TMZ-resistant GBM cell lines and primary cultures of newly diagnosed GBM with different MGMT promoter methylation status, phenotypic/genotypic background and subtype, and validated with sphere formation, cell migration assays, and quantitative invasive orthotopic in vivo models. Results: We identified hydroxyurea (HU) to synergize with TMZ in GBM cells in culture and in vivo, irrespective of MGMT promoter methylation status, subtype, and/or stemness. HU acts specifically on the S-phase of the cell cycle by inhibiting the M2 unit of enzyme ribonucleotide reductase. Knockdown of this enzyme using RNA interference and other known chemical inhibitors exerted a similar effect to HU in combination with TMZ both in culture and in vivo. Conclusions: We demonstrate preclinical efficacy of repurposing hydroxyurea in combination with TMZ for adjuvant GBM therapy. This combination benefit is of direct clinical interest given the extensive use of TMZ and the associated problems with TMZ-related resistance and treatment failure.
Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Replicação do DNA/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Hidroxiureia/farmacologia , Temozolomida/farmacologia , Animais , Antineoplásicos Alquilantes/farmacologia , Apoptose , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proliferação de Células , Reposicionamento de Medicamentos , Glioblastoma/classificação , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Novel 4'-substituted ß-d-2'-deoxy-2'-α-fluoro (2'd2'F) nucleoside inhibitors of respiratory syncytial virus (RSV) are reported. The introduction of 4'-substitution onto 2'd2'F nucleoside analogs resulted in compounds demonstrating potent cell based RSV inhibition, improved inhibition of the RSV polymerase by the nucleoside triphosphate metabolites, and enhanced selectivity over incorporation by mitochondrial RNA and DNA polymerases. Selectivity over the mitochondrial polymerases was found to be extremely sensitive to the specific 4'-substitution and not readily predictable. Combining the most potent and selective 4'-groups from N-nucleoside analogs onto a 2'd2'F C-nucleoside analog resulted in the identification of ß-D-2'-deoxy-2'-α-fluoro-4'-α-cyano-5-aza-7,9-dideaza adenosine as a promising nucleoside lead for RSV.
Assuntos
Adenosina/química , Antivirais/química , DNA Polimerase Dirigida por DNA/química , Inibidores da Síntese de Ácido Nucleico/química , RNA Polimerase Dependente de RNA/antagonistas & inibidores , RNA/química , Vírus Sinciciais Respiratórios/enzimologia , Vírus Sinciciais Respiratórios/fisiologia , Adenosina/síntese química , Adenosina/farmacologia , Antivirais/síntese química , Antivirais/farmacologia , Compostos Aza/química , DNA Polimerase Dirigida por DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos , Inibidores da Síntese de Ácido Nucleico/síntese química , Inibidores da Síntese de Ácido Nucleico/farmacologia , RNA/metabolismo , RNA Mitocondrial , RNA Polimerase Dependente de RNA/metabolismo , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
Protected N-branched nucleoside phosphonates containing adenine and thymine bases were prepared as the monomers for the introduction of aza-acyclic nucleotide units into modified oligonucleotides. The phosphotriester and phosphoramidite methods were used for the incorporation of modified and natural units, respectively. The solid phase synthesis of a series of nonamers containing one central modified unit was successfully performed in both 3'â5' and 5'â3' directions. Hybridization properties of the prepared oligoribonucleotides and oligodeoxyribonucleotides were evaluated. The measurement of thermal characteristics of the complexes of modified nonamers with the complementary strand revealed a considerable destabilizing effect of the introduced units. We also examined the substrate/inhibitory properties of aza-acyclic nucleoside phosphono-diphosphate derivatives (analogues of nucleoside triphosphates) but neither inhibition of human and bacterial DNA polymerases nor polymerase-mediated incorporation of these triphosphate analogues into short DNA was observed.
Assuntos
Inibidores da Síntese de Ácido Nucleico/química , Nucleosídeos/química , Oligonucleotídeos/química , Organofosfonatos/química , Adenina/síntese química , Adenina/química , Sequência de Bases , DNA Polimerase Dirigida por DNA/metabolismo , Humanos , Inibidores da Síntese de Ácido Nucleico/síntese química , Inibidores da Síntese de Ácido Nucleico/farmacologia , Nucleosídeos/síntese química , Nucleosídeos/farmacologia , Oligonucleotídeos/síntese química , Oligonucleotídeos/farmacologia , Organofosfonatos/síntese química , Organofosfonatos/farmacologia , Timina/síntese química , Timina/químicaRESUMO
Epigallocatechin gallate (EGCG), ellagic acid (EA) and rosmarinic acid (RA) are natural polyphenols exerting cancer chemopreventive effects. Ribonucleotide reductase (RR; EC 1.17.4.1) converts ribonucleoside diphosphates into deoxyribonucleoside diphosphates being essential for DNA replication, which is why the enzyme is considered an excellent target for anticancer therapy. EGCG, EA, and RA dose-dependently inhibited the growth of human HL-60 promyelocytic leukemia cells, exerted strong free radical scavenging potential, and significantly imbalanced nuclear deoxyribonucleoside triphosphate (dNTP) concentrations without distinctly affecting the protein levels of RR subunits (R1, R2, p53R2). Incorporation of (14)C-cytidine into nascent DNA of tumor cells was also significantly lowered, being equivalent to an inhibition of DNA synthesis. Consequently, treatment with EGCG and RA attenuated cells in the G0/G1 phase of the cell cycle, finally resulting in a pronounced induction of apoptosis. Sequential combination of EA and RA with the first-line antileukemic agent arabinofuranosylcytosine (AraC) synergistically potentiated the antiproliferative effect of AraC, whereas EGCG plus AraC yielded additive effects. Taken together, we show for the first time that EGCG, EA, and RA perturbed dNTP levels and inhibited cell proliferation in human HL-60 promyelocytic leukemia cells, with EGCG and RA causing a pronounced induction of apoptosis. Due to these effects and synergism with AraC, these food ingredients deserve further preclinical and in vivo testing as inhibitors of leukemic cell proliferation.
Assuntos
Antineoplásicos/farmacologia , Catequina/análogos & derivados , Cinamatos/farmacologia , Citarabina/farmacologia , Depsídeos/farmacologia , Ácido Elágico/farmacologia , Trifosfato de Adenosina/química , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , DNA/biossíntese , Sinergismo Farmacológico , Sequestradores de Radicais Livres/farmacologia , Células HL-60/efeitos dos fármacos , Humanos , Estrutura Molecular , Inibidores da Síntese de Ácido Nucleico/farmacologia , Nucleotídeos de Timina/química , Ácido RosmarínicoRESUMO
PURPOSE: To test 2 strategies to prevent capsule opacification after accommodating lens refilling in a rhesus monkey model. SETTING: Animal laboratory and laboratory of European university medical centers. DESIGN: Experimental study. METHODS: Six rhesus monkeys had refilling of the lens capsular bag. In the first strategy, before it was filled with a silicone polymer, the capsular bag was treated with noncommercial sodium hyaluronate 1.0% containing cytotoxic substances. In the second strategy, the capsular bag was filled with clinically used sodium hyaluronate 1.0% (Healon) after treatment with actinomycin-D. Slitlamp inspection was performed during a follow-up of 40 to 50 weeks. After enucleation, magnetic resonance images were obtained and confocal fluorescence imaging was performed. RESULTS: Using the first strategy, capsule opacification developed in all eyes. Using the second strategy, 1 monkey did not develop capsule opacification after a 9-month follow-up. In a second monkey, the lens capsule remained clear for 3 months, after which the hyaluronate refill material was exchanged with a silicone polymer and capsule opacification developed. Combining these results with those in a previous study, the difference in opacification between silicone and sodium hyaluronate as refilling materials was statistically significant (P<.01). CONCLUSIONS: That no capsular bag fibrosis occurred in the presence of hyaluronate suggests that the properties of hyaluronate are the reason that remaining lens epithelial cells do not develop into fibrotic cells. The choice of a suitable lens-refilling material prevents the development of capsule opacification. FINANCIAL DISCLOSURE: Mr. Terwee was an employee of Abbott Medical Optics B.V. during the study period. No other author has a financial or proprietary interest in any material or method mentioned.
Assuntos
Opacificação da Cápsula/prevenção & controle , Dactinomicina/farmacologia , Ácido Hialurônico/farmacologia , Cápsula do Cristalino/efeitos dos fármacos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Elastômeros de Silicone/administração & dosagem , Viscossuplementos/farmacologia , Acomodação Ocular , Animais , Modelos Animais de Doenças , Combinação de Medicamentos , Feminino , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Projetos PilotoRESUMO
Recent epidemiological studies have shown that moderate coffee consumption is associated with a lower risk of certain types of cancers, particularly colon cancer in postmenopausal women. To elucidate the molecular basis for the preventive action of coffee, we investigated the effect of coffee on estrogen sulfotransferase (SULT) because sulfation is the major pathway involved in the inactivation of estrogens. We found that coffee reduced SULT1E1 gene expression in human colon carcinoma Caco-2 cells. Treatment with 2.5% (v/v) coffee for 24 h resulted in a 60% reduction of the expression of the SULT1E1 gene in Caco-2 cells. Corresponding to reduced SULT1E1 gene expression, cytosolic estrogen SULT activity toward E(2) (20 nM) decreased by 25%. In addition, an accumulation of E(2) sulfates in the medium, which reflects cellular activity of estrogen SULT, decreased after the cells were treated with coffee. Major bioactive constituents in coffee such as caffeine, chlorogenic acid and caffeic acid did not show any effect. The inhibitory activity was extractable by using ethyl acetate. We also found that the inhibitory activity was produced by roasting the coffee beans. Mithramycin, an inhibitor of the transcription factor stimulating protein 1 (Sp1), was able to restore coffee-reduced SULT1E1 gene expression. Our data suggest that daily coffee consumption may reduce estrogen SULT activity, thereby enhancing estrogenic activity in the colon.
Assuntos
Coffea , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sulfotransferases/genética , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Café , Neoplasias do Colo/enzimologia , Estradiol/metabolismo , Humanos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Plicamicina/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Fator de Transcrição Sp1/antagonistas & inibidores , Sulfotransferases/metabolismoRESUMO
Resveratrol (3,4',5-trihydroxy-trans-stilbene), one of secondary metabolites of low molecular weight present in plant, has various important biological effects. It can induce apoptosis in human leukemia cell types in vitro, although the mechanism is not fully understood. In the present study, we demonstrated reduced viability and DNA synthesis, as well as increased proportion of the subdiploid cell population, in HL-60 cells as determined by cell cycle analysis with resveratrol. Resveratrol treatment resulted in a gradual time-dependent decrease in the expression of anti-apoptotic Bcl-2 and increase in that of Bax, annexin A1, growth arrest- and DNA damage-induced gene 45α (GADD45α), and cleaved caspase-3. In addition, resveratrol markedly increased caspase-3 activity in cells. Our results suggest that resveratrol could inhibit the proliferation and induce apoptosis of HL-60 cells through a GADD45α and annexin A1/caspase-3 pathway.
Assuntos
Anexina A1/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Proteínas Nucleares/metabolismo , Estilbenos/farmacologia , Anexina A1/biossíntese , Anexina A1/genética , Apoptose/fisiologia , Caspase 3/metabolismo , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Processos de Crescimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Fase G1/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Inibidores da Síntese de Ácido Nucleico/farmacologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , ResveratrolRESUMO
Eight-month old WAG/Rij rats, which developed spontaneous occurring absence seizures, showed a reduced function of mGlu1 metabotropic glutamate receptors in the thalamus, as assessed by in vivo measurements of DHPG-stimulated polyphosphoinositide hydrolysis, in the presence of the mGlu5 antagonist MPEP as compared to age-matched non-epileptic control rats. These symptomatic 8-month old WAG/Rij rats also showed lower levels of thalamic mGlu1α receptors than age-matched controls and 2-month old (pre-symptomatic) WAG/Rij rats, as detected by immunoblotting. Immunohistochemical and in situ hybridization analysis indicated that the reduced expression of mGlu1 receptors found in symptomatic WAG/Rij rats was confined to an area of the thalamus that excluded the ventroposterolateral nucleus. No mGlu1 receptor mRNA was detected in the reticular thalamic nucleus. Pharmacological manipulation of mGlu1 receptors had a strong impact on absence seizures in WAG/Rij rats. Systemic treatment with the mGlu1 receptor enhancer SYN119, corresponding to compound RO0711401, reduced spontaneous spike and wave discharges spike-wave discharges (SWDs) in epileptic rats. Subcutaneous doses of 10 mg/kg of SYN119 only reduced the incidence of SWDs, whereas higher doses (30 mg/kg) also reduced the mean duration of SWDs. In contrast, treatment with the non-competitive mGlu1 receptor antagonist, JNJ16259685 (2.5 and 5 mg/kg, i.p.) increased the incidence of SWDs. These data suggest that absence epilepsy might be associated with a reduction of mGlu1 receptors in the thalamus, and that compounds that amplify the activity of mGlu1 receptors might be developed as novel anti-absence drugs. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.
Assuntos
Epilepsia Tipo Ausência/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Regulação Alostérica , Animais , Ciprofloxacina/análogos & derivados , Ciprofloxacina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Epilepsia Tipo Ausência/tratamento farmacológico , Epilepsia Tipo Ausência/genética , Antagonistas de Aminoácidos Excitatórios/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Quinolinas/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos , Receptores de Glutamato Metabotrópico/genética , Transdução de Sinais/efeitos dos fármacos , Núcleos Talâmicos/metabolismo , Núcleos Talâmicos/fisiopatologia , Tálamo/metabolismo , Tálamo/fisiopatologiaRESUMO
Recent research has shown that the maternal nucleolus is essential for embryonic development. The morphology of the nucleolus in growing oocytes differs from that in full-grown oocytes. We determined the ability of nucleoli from growing oocytes to substitute for nucleoli of full-grown oocytes in terms of supporting embryonic development in this study. Growing (around 100 microm in diameter) and full-grown porcine oocytes (120 microm) were collected from small (0.6-1.0 mm) and large antral follicles (4-5 mm), respectively. The nucleolus was aspirated from full-grown oocytes by micromanipulation, and the resulting enucleolated oocytes were matured to metaphase II; the nucleoli originating from full-grown and growing oocytes were then injected into the oocytes. The Chromatin of growing oocytes was aspirated with the nucleolus during the enucleolation process. Growing oocytes were thus treated with actinomycin D to release the chromatin from their nucleoli, and the nucleoli were collected and transferred to the enucleolated and matured full-grown oocytes. After activation by electro-stimulation, nucleoli were formed in pronuclei of sham-operated oocytes. Enucleolated oocytes that had been injected with nucleoli from either full-grown or growing, however, did not form any nucleoli in the pronuclei. No enucleolated oocytes developed to blastocysts, whereas enucleolated oocytes injected with nucleoli from full-grown oocytes (15%) or growing oocytes (18%) developed to blastocysts. These results indicate that the nucleoli from growing oocytes can substitute for nucleoli from full-grown oocytes during early embryonic development.
Assuntos
Nucléolo Celular/metabolismo , Cromatina/metabolismo , Oócitos/metabolismo , Animais , Blastocisto/citologia , Blastocisto/metabolismo , Nucléolo Celular/efeitos dos fármacos , Nucléolo Celular/fisiologia , Nucléolo Celular/transplante , Dactinomicina/farmacologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Metáfase/efeitos dos fármacos , Inibidores da Síntese de Ácido Nucleico/farmacologia , Oócitos/citologia , SuínosRESUMO
Antrodia camphorata, unique fungal specie, has been used as a folk medicine in Taiwan for many years. The purpose of this study was to compare the extracts from the solid-state culture of A. camphorata co-fermented with Chinese medicinal herb (AC-CF) with two other extracts from fruiting bodies (AC-FB) or solid-state culture (AC-SS), for their anti-tumor effects in human hepatoma HepG2 cells. We measured in vitro cell proliferation, percentage of apoptosis, population distribution of cell cycles, Western blot analysis of multiple drugs resistance-1 (MDR-1), and apoptosis-related proteins in HepG2 cells treated with three different preparations of A. camphorate extracts. Our results showed that AC-CF had better anti-proliferation effect on human hepatoma HepG2 cells than AC-FB or AC-SS dose-dependently. In addition, AC-CF in combination with anti-tumor agents (mitomycin C or methotrexate) showed better adjuvant anti-tumor effects than AC-FB or AC-SS. We further demonstrated the augmented adjuvant anti-tumor effects of AC-CF not only through down regulation of MDR-1 expression but also through a COX-2 dependent apoptosis pathway, involving down-regulation of COX-2 and p-AKT and up-regulation of PARP-1. In conclusion, in this study, we have demonstrated a novel strategy of fermenting A. camphorata with Chinese medicinal herb (AC-CF), which augmented their anti-tumor effects in human hepatoma HepG2 cells as compared to the traditional ones (AC-FB or AC-SS).