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1.
Eur J Med Chem ; 188: 112009, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31883488

RESUMO

SRO-91 is a non-natural ribofuranosyl-1,2,3-triazole C-nucleoside obtained by a synthetic sequence involving a C-alkynyl glycosylation mediated by metallic indium and a Huisgen cycloaddition for the construction of the triazole. Its structure is close to the one of ribavirin, a drug presenting a broad-spectrum against viral infections. SRO-91 antitumor activities were investigated on 9 strains of tumor cells and IC50 of the order of 1 µM were obtained on A431 epidermoid carcinoma cells and B16F10 skin melanoma cells. In addition, studies of ovarian tumor cell inhibitions show an interesting activity in regard to the need for new drugs for this pathology. Finally, cytotoxicity and mouse toxicity studies reveal a favorable therapeutic index for SRO-91.


Assuntos
Antineoplásicos/farmacologia , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Linhagem Celular Transformada , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos , Ribavirina/toxicidade
2.
Appl Biochem Biotechnol ; 190(1): 305-324, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31346920

RESUMO

Current estimates indicate that hepatocarcinoma is the leading cause of death globally. There is interest in utilizing nanomedicine for cancer therapy to overcome side effects of chemo-interventions. Ribavirin, an antiviral nucleoside inhibitor, accumulates inside red blood cells, causing anemia. Its analog, viramidine, can concentrate within hepatocytes and spare red blood cells, thus limiting anemia. Hepatocarcinoma cells have a large number of asialoglycoprotein receptors on their membranes that can bind galactosyl-terminating solid lipid nanoparticles (Gal-SLN) and internalize them. Here, viramidine, 5-fluorouracil, and paclitaxel-loaded Gal-SLN were characterized inside cells. Cytotoxicities of free-drug, nano-void, and drug-loaded Gal-SLN were evaluated using HepG2 cells; over 3 days, cell viability was measured. To test the mechanistic pathway, we investigated in vitro apoptosis using flow cytometry and in ovo angiogenesis using the CAM assay. Results showed that 1 and 2 µM of the viramidine-encapsulated Gal-SLN had the highest cytotoxic effect, achieving 80% cell death with a steady increase over 3 days, with induction of apoptosis and reduction of necrosis and angiogenesis, compared to free-drugs. Gal-SLN application on breast cancer MCF-7 cells confirmed its specificity against liver cancer HepG2 cells. We conclude that viramidine-encapsulated Gal-SLN has anticancer and anti-angiogenic activities against hepatocarcinoma.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Apoptose/efeitos dos fármacos , Galactose/química , Nanopartículas/química , Neovascularização Patológica/prevenção & controle , Ribavirina/análogos & derivados , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Células Hep G2 , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Células MCF-7 , Ribavirina/administração & dosagem , Ribavirina/química , Ribavirina/farmacologia
3.
Eur J Med Chem ; 183: 111712, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31557614

RESUMO

Three novel tiazofurin analogues having d-arabino stereochemistry and nitrogen functionalities at the C-2' position (5-7) have been designed and synthesized in multistep sequences, starting from d-glucose. The known d-xylo stereoisomer of 1 (compound 2) along with two new analogues bearing nitrogen functions at the C-3' (3 and 4) has also been synthesized from the same sugar precursor. The synthetic sequence consisted of the following three stages: (i) the multistep synthesis of suitably protected pentofuranosyl cyanides, (ii) the construction of ethyl thiazole-4-carboxylate part by cyclocondensation of thus obtained glycofuranosyl cyanides with l-cysteine ethyl ester followed by dehydrogenation, and (iii) the final transformation of the ethyl thiazole-4-carboxylates into the target tiazofurin analogues using the esters ammonolysis. The tiazofurin analogues were evaluated for their antitumour activities in cell-culture-based assays. Compounds 3, 4 (d-xylo) and 7 (d-arabino), showed remarkable antitumour activities, with IC50 values in the range of 4-7 nM. Preliminary structure-activity relationship allowed identification of two analogues with antiproliferative activities exceeding that of the parent compound 1 for several orders of magnitude (e.g. 4: 1354-fold against Raji, 7: 309-fold against K562). Flow cytometry data and Western blot analysis suggested that cytotoxic effects of d-xylo stereoisomers in the culture of K562 cells caused changes in the cell cycle distribution, as well as the induction of apoptosis in caspase-dependent way. The increase of apoptotic cells percentage in treated samples is also confirmed with fluorescent double-staining method. Genotoxicity testing showed that the analogues with the xylo-configuration (2-4) are far less genotoxic than tiazofurin.


Assuntos
Antineoplásicos , Desenho de Fármacos , Ribavirina/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células K562 , Nitrogênio/química , Ribavirina/síntese química , Ribavirina/química , Ribavirina/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
4.
Pharm Res ; 35(4): 76, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29488022

RESUMO

PURPOSE: Breast cancer is the second most common cause of mortality in women in the United States. Targeted delivery of antitumor breast cancer drugs as a drug-delivery strategy may allow direct delivery into the tumor. Currently, chemotherapy is one of the principle strategies for cancer treatment, but it can have toxic side effects. Nanotechnology attempts to resolve these challenges by loading drugs in nanoparticles, such as solid lipid nanoparticles (SLN). In response to the breast cancer drug 5-fluorouracil (5-FU), p38MAPK signaling has been investigated since the 1990s. Ribavirin, a nucleotide derivative, inhibits p38MAPK in infected hepatocytes. A ribavirin prodrug, taribavirin (TBV), was recently synthesized to concentrate in the liver and have minimal concentration in red blood cells. METHODS: In this study, TBV and 5-FU-pegylated SLNs were prepared and characterized. The in vitro cytotoxicity was evaluated against MCF-7 breast cancer cells. Using molecular docking experiments, 5-FU and TBV were docked on p38MAPK protein. RESULTS: The TBV nanoformulation had the highest cytotoxic effects, achieving IC50 = 0.690 µM after 24 h, compared with free TBV, which also achieved a good cytotoxic effect (IC50 = 0.756 µM). However, there was a detectable cytotoxic effect and an undetectable IC50 of 5-FU nanoparticles and free 5-FU on MCF-7 cells. CONCLUSIONS: The effect of TBV nanoparticles on MCF-7 cells may be due to its inhibitory effect against p38MAPK protein, where it fits inside the active pocket site of the p38 protein molecular surface, with a minimum binding affinity of -5.5 kcal/mol (rmsd of 1.07), and it formed strong hydrogen bonds with amino acids ASP'168, ILE'166, HIS'148, and ILE'147. Further studies are warranted to investigate the mechanistic details of the proposed approach.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Fluoruracila/farmacologia , Proteína Quinase 14 Ativada por Mitógeno/antagonistas & inibidores , Ribavirina/análogos & derivados , Antineoplásicos/química , Disponibilidade Biológica , Neoplasias da Mama/patologia , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/química , Humanos , Concentração Inibidora 50 , Lipídeos/química , Células MCF-7 , Proteína Quinase 14 Ativada por Mitógeno/química , Proteína Quinase 14 Ativada por Mitógeno/metabolismo , Simulação de Acoplamento Molecular , Nanopartículas/química , Polietilenoglicóis/química , Ribavirina/química , Ribavirina/farmacologia
5.
Exp Cell Res ; 350(1): 32-40, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27818246

RESUMO

We investigated the role of autophagy, a process of controlled self-digestion, in the in vitro anticancer action of the inosine monophosphate dehydrogenase (IMPDH) inhibitor ribavirin. Ribavirin-triggered oxidative stress, caspase activation, and apoptotic death in U251 human glioma cells were associated with the induction of autophagy, as confirmed by intracellular acidification, appearance of autophagic vesicles, conversion of microtubule associated protein 1 light chain 3 (LC3)-I to autophagosome-associated LC3-II, and degradation of autophagic target p62/sequestosome 1. Ribavirin downregulated the activity of autophagy-inhibiting mammalian target of rapamycin complex 1 (mTORC1), as indicated by a decrease in phosphorylation of the mTORC1 substrate ribosomal p70S6 kinase and reduction of the mTORC1-activating Src/Akt signaling. Guanosine supplementation inhibited, while IMPDH inhibitor tiazofurin mimicked ribavirin-mediated autophagy induction, suggesting the involvement of IMPDH blockade in the observed effect. Autophagy suppression by ammonium chloride, bafilomycin A1, or RNA interference-mediated knockdown of LC3 sensitized glioma cells to ribavirin-induced apoptosis. Ribavirin also induced cytoprotective autophagy associated with Akt/mTORC1 inhibition in C6 rat glioma cells. Our data demonstrate that ribavirin-triggered Akt/mTORC1-dependent autophagy counteracts apoptotic death of glioma cells, indicating autophagy suppression as a plausible therapeutic strategy for sensitization of cancer cells to IMPDH inhibition.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Glioma/enzimologia , IMP Desidrogenase/antagonistas & inibidores , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Glioma/genética , Glioma/patologia , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Transdução de Sinais/efeitos dos fármacos
6.
Eur J Med Chem ; 111: 114-25, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-26859071

RESUMO

Synthesis of three tiazofurin (1) isosteres with nitrogen functionalities at the C-2' position (N3, NH2 and NH3(+)Cl(-)) has been achieved, in multistep sequences, starting from monoacetone d-glucose. A number of potential bioisosteres of 1 bearing acylamido functions at the C-2' position have also been synthesized from the same sugar precursor. In vitro cytotoxicities of target molecules against a number of human tumour cell lines were recorded and compared with those observed for lead molecule 1. Some of the synthesized compounds showed potent in vitro antitumour activity, such as 2'-azido derivative 2, which is the most potent of all molecules under evaluation (IC50 0.004 µM against MCF-7 cells). Flow cytometry data suggest that cytotoxic effects of these compounds in the culture of K562 cells might be mediated by apoptosis, additionally revealing that these molecules induced changes in cell cycle distribution of these cells. Results of Western blot analysis indicate that the synthesized tiazofurin analogues induce apoptosis in a caspase-dependent way.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Ribavirina/análogos & derivados , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Ribavirina/síntese química , Ribavirina/química , Ribavirina/farmacologia , Relação Estrutura-Atividade
7.
Antivir Chem Chemother ; 23(4): 161-71, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23538746

RESUMO

BACKGROUND: Ribavirin is a broad-spectrum antiviral agent that derives some of its activity from inhibition of cellular inosine monophosphate dehydrogenase (IMPDH), resulting in lower guanosine triphosphate (GTP) levels. Here we report the biological activities of three ribavirin analogues. METHODS: Antiviral activities of test compounds were performed by in vitro cytopathic effect inhibition assays against influenza A (H1N1, H3N2 and H5N1), influenza B, measles, parainfluenza type 3 (PIV-3) and respiratory syncytial viruses. Compounds were modelled into the ribavirin 5'-monophosphate binding site of the crystallographic structure of the human type II IMPDH (hIMPDH2) ternary complex. Effects of compounds on intracellular GTP levels were performed by strong anion exchange HPLC analysis. RESULTS: Of the three compounds evaluated, the 5-ethynyl nucleoside (ETCAR) exhibited virus-inhibitory activities (at 1.2-20 µM, depending upon the virus) against most of the viruses, except for weak activity against PIV-3 (62 µM). Antiviral activity of ETCAR was similar to ribavirin; however, cytotoxicity of ETCAR was greater than ribavirin. Replacing the 5-ethynyl group with a 5-propynyl or bromo substituent (BrCAR) considerably reduced antiviral activity. Computational studies of ternary complexes of hIMPDH2 enzyme with 5'-monophosphates of the compounds helped rationalize the observed differences in biological activity. All compounds suppressed GTP levels in cells; additionally, BrCAR suppressed adenosine triphosphate and elevated uridine triphosphate levels. CONCLUSIONS: Three compounds related to ribavirin inhibited IMPDH and had weak to moderate antiviral activity. Cytotoxicity adversely affected the antiviral selectivity of ETCAR. As with ribavirin, reduction in intracellular GTP may play a role in virus inhibition.


Assuntos
Antivirais/química , Antivirais/farmacologia , Nucleosídeos/química , Nucleosídeos/farmacologia , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Animais , Linhagem Celular , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Vírus da Influenza B/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , Sarampo/tratamento farmacológico , Vírus do Sarampo/efeitos dos fármacos , Modelos Moleculares , Infecções por Orthomyxoviridae/tratamento farmacológico , Vírus da Parainfluenza 3 Humana/efeitos dos fármacos , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Infecções por Respirovirus/tratamento farmacológico , Triazóis/química , Triazóis/farmacologia
8.
PLoS One ; 8(7): e68347, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874596

RESUMO

T-705 (Favipiravir) is a broad-spectrum antiviral molecule currently in late stage clinical development for the treatment of influenza virus infection. Although it is believed that T-705 potency is mediated by its ribofuranosyl triphosphate (T-705 RTP) metabolite that could be mutagenic, the exact molecular interaction with the polymerase of influenza A virus (IAVpol) has not been elucidated. Here, we developed a biochemical assay to measure the kinetics of nucleotide incorporation by IAVpol in the elongation mode. In this assay, T-705 RTP was recognized by IAVpol as an efficient substrate for incorporation to the RNA both as a guanosine and an adenosine analog. Compared to natural GTP and ATP, the discrimination of T-705 RTP was about 19- and 30-fold, respectively. Although the single incorporation of the ribonucleotide monophosphate form of T-705 did not efficiently block RNA synthesis, two consecutive incorporation events prevented further primer extension. In comparison, 3'-deoxy GTP caused immediate chain termination but was incorporated less efficiently by the enzyme, with a discrimination of 4,900-fold relative to natural GTP. Collectively, these results provide the first detailed biochemical characterization to evaluate the substrate efficiency and the inhibition potency of nucleotide analogs against influenza virus polymerase. The combination of ambiguous base-pairing with low discrimination of T-705 RTP provides a mechanistic basis for the in vitro mutagenic effect of T-705 towards influenza virus.


Assuntos
Amidas/farmacologia , Antivirais/farmacologia , Pareamento Incorreto de Bases , Pareamento de Bases/efeitos dos fármacos , DNA Polimerase Dirigida por DNA/metabolismo , Vírus da Influenza A/enzimologia , Pirazinas/farmacologia , Amidas/metabolismo , Animais , Antimetabólitos/metabolismo , Antimetabólitos/farmacologia , Antivirais/metabolismo , Pareamento Incorreto de Bases/efeitos dos fármacos , Pareamento Incorreto de Bases/fisiologia , DNA Polimerase Dirigida por DNA/efeitos dos fármacos , Humanos , Polifosfatos/metabolismo , Polifosfatos/farmacologia , Pirazinas/metabolismo , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Células Sf9 , Spodoptera , Especificidade por Substrato
9.
Cancer Gene Ther ; 20(7): 403-12, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23764899

RESUMO

Colorectal cancer cells exhibit limited cytotoxicity towards Tiazofurin, a pro-drug metabolized by cytosolic nicotinamide mononucleotide adenylyltransferase2 (NMNAT2) to thiazole-4-carboxamide adenine dinucleotide, a potent inhibitor of inosine 5'-monophosphate dehydrogenase required for cellular guanylate synthesis. We tested the hypothesis that colorectal cancer cells that exhibit low levels of NMNAT2 and are refractory to Tiazofurin can be rendered sensitive to Tiazofurin by overexpressing NMNAT2. Transfection of hNMNAT2 resulted in a six- and threefold cytoplasmic overexpression in Caco2 and HT29 cell lines correlating with Tiazofurin-induced enhanced cell-kill. Folate receptors expressed on the cell surface of 30-50% colorectal carcinomas were exploited for cellular targeting with Tiazofurin encapsulated in folate-tethered nanoparticles. Our results indicated that in wild-type colorectal cancer cells, free Tiazofurin-induced EC50 cell-kill was 1500-2000 µM, which was reduced to 66-156 µM in hNMNAT2-overexpressed cells treated with Tiazofurin encapsulated in non-targeted nanoparticles. This efficacy was improved threefold by encapsulating Tiazofurin in folate-tethered nanoparticles to obtain an EC(50) cell-kill of 22-59 µM, an equivalent of 100-300 mg m(-2) (one-tenth of the approved dose of Tiazofurin in humans), which will result in minimal toxicity leading to cancer cell-kill. This proof-of-principle study suggests that resistance of colorectal cancer cell-kill to Tiazofurin can be overcome by sequentially overexpressing hNMNAT2 and then facilitating the uptake of Tiazofurin by folate-tethered nanoparticles, which enter cells via folate receptors.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Expressão Gênica , Nicotinamida-Nucleotídeo Adenililtransferase/metabolismo , Ribavirina/análogos & derivados , Antimetabólitos Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais , Portadores de Fármacos/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fluoresceínas/metabolismo , Transportadores de Ácido Fólico/metabolismo , Técnicas de Silenciamento de Genes , Guanosina Trifosfato/metabolismo , Humanos , IMP Desidrogenase/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , Nanopartículas/metabolismo , Nicotinamida-Nucleotídeo Adenililtransferase/genética , Transporte Proteico , RNA Interferente Pequeno/genética , Ribavirina/metabolismo , Ribavirina/farmacologia , Transfecção
10.
Antivir Ther ; 17(7): 1311-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22951364

RESUMO

BACKGROUND: Today, treatment of chronic hepatitis C is based on a synergistic combination of pegylated interferon and ribavirin with antiprotease inhibitors. Haemolytic anaemia, which is the major side effect of ribavirin treatment, disrupts ribavirin treatment compliance and varies significantly from one patient to another. There is an individual susceptibility to ribavirin haemolysis. With a view to studying haemolysis, and thus optimizing the treatment response, we have developed a new in vitro tool for analysing the ribavirin-induced lysis of red blood cells. METHODS: Resuspended red blood cells were incubated with isotonic buffer and a range of concentrations of ribavirin. Haemolysis was quantified by spectrophotometric measurement of the supernatant at 540 nm. The assay was used to test the effects of various compounds and to investigate the susceptibility of patients to haemolytic anaemia. RESULTS: In our assay, the degree of haemolysis is dependent on the ribavirin concentration used and can be inhibited by the addition of dipyridamole (50% inhibitory concentration [IC(50)] 30 µM), ATP or glutathione (IC(50) 1.63 mM and 767 µM, respectively). We observed a strong decrease in red blood cell haemolysis in the presence of the ribavirin prodrug viramidine (Taribavirin(®)). When testing the performance of this assay with blood from 24 patients before treatment, we observed a strong correlation between in vitro haemolysis before treatment and the decrease in haemoglobin levels seen in vivo during subsequent treatment (P<0.001). CONCLUSIONS: With this new tool it is possible to better evaluate individual susceptibility to ribavirin-induced haemolysis before the start of treatment. In addition, this model will enable the mechanism of ribavirin-induced anaemia to be further explored and allow molecules that could reduce ribavirin haemolysis to be screened and tested in vitro. This approach could help optimize current and future therapeutic strategies involving ribavirin in the treatment of chronic hepatitis C.


Assuntos
Eritrócitos/efeitos dos fármacos , Hemólise , Ribavirina/efeitos adversos , Trifosfato de Adenosina/farmacologia , Adulto , Anemia Hemolítica/induzido quimicamente , Anemia Hemolítica/patologia , Dipiridamol/farmacologia , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Glutationa/farmacologia , Testes Hematológicos/métodos , Hepacivirus/genética , Hepacivirus/patogenicidade , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Concentração Inibidora 50 , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacologia , Poliovirus/efeitos dos fármacos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacologia , Pró-Fármacos/farmacologia , RNA Viral/sangue , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Ribavirina/administração & dosagem , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Ribavirina/uso terapêutico
11.
Bioanalysis ; 4(15): 1895-905, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22943620

RESUMO

BACKGROUND: The polar nucleoside drug ribavirin (RBV) combined with IFN-α is a front-line treatment for chronic hepatitis C virus infection. RBV acts as a prodrug and exerts its broad antiviral activity primarily through its active phosphorylated metabolite ribavirin 5´-triphosphate (RTP), and also possibly through ribavirin 5´-monophosphate (RMP). To study RBV transport, diffusion, metabolic clearance and its impact on drug-metabolizing enzymes, a LC-MS method is needed to simultaneously quantify RBV and its phosphorylated metabolites (RTP, ribavirin 5´-diphosphate and RMP). In a recombinant human UGT1A1 assay, the assay buffer components uridine and its phosphorylated derivatives are isobaric with RBV and its phosphorylated metabolites, leading to significant interference when analyzed by LC-MS with the nominal mass resolution mode. RESULTS: Presented here is a LC-MS method employing LC coupled with full-scan high-resolution accurate MS analysis for the simultaneous quantitative determination of RBV, RMP, ribavirin 5´-diphosphate and RTP by differentiating RBV and its phosphorylated metabolites from uridine and its phosphorylated derivatives by accurate mass, thus avoiding interference. CONCLUSION: The developed LC-high-resolution accurate MS method allows for quantitation of RBV and its phosphorylated metabolites, eliminating the interferences from uridine and its phosphorylated derivatives in recombinant human UGT1A1 assays.


Assuntos
Antivirais/análise , Antivirais/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Ribavirina/análise , Ribavirina/farmacocinética , Espectrometria de Massas por Ionização por Electrospray/métodos , Monofosfato de Adenosina , Cromatografia por Troca Iônica/métodos , Glucuronosiltransferase/análise , Glucuronosiltransferase/metabolismo , Hepatite C Crônica/tratamento farmacológico , Humanos , Nucleotídeos/análise , Ribavirina/análogos & derivados , Uridina/análise , Difosfato de Uridina/análise , Uridina Monofosfato/análise
12.
Bioorg Med Chem Lett ; 22(21): 6700-4, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010263

RESUMO

2-(ß-D-xylofuranosyl)thiazole-4-carboxamide (2) and two new tiazofurin analogues with 5-hydroxymethyl-2-methyl-tetrahydro-furo[2,3-d][1,3]dioxol-6-ol moiety as a sugar mimic (27 and 28) have been synthesized and evaluated for their in vitro antitumour activity against a panel of human tumour cell lines (K562, HL 60, Jurkat, Raji and HeLa). In contrast to previous literature reports, a metabolic MTT assay revealed remarkable cytotoxicity of 2 against K562 (IC(50)=0.15 µM) and HL-60 (IC(50)=0.13 µM) cells. Flow cytometry data suggest that cytotoxic effects of analogue 2 in the culture of K562 cells might be mediated by apoptosis, in opposite to tiazofurin, which did not induce apoptosis of K562 cells after 24h, thus suggesting a different mechanism of action. All three analogues 2, 27 and 28 were also active against Jurkat, Raji and HeLa cells, with IC(50) values in the range from 0.06 to 5.61 µM, but were completely inactive against the normal foetal lung fibroblasts (MRC-5).


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Nucleosídeos/síntese química , Ribavirina/análogos & derivados , Antineoplásicos/química , Carboidratos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Mimetismo Molecular , Estrutura Molecular , Nucleosídeos/química , Nucleosídeos/farmacologia , Ribavirina/síntese química , Ribavirina/química , Ribavirina/farmacologia , Tiazóis/síntese química , Tiazóis/química , Tiazóis/farmacologia , Xilose/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-22257212

RESUMO

The novel aza-analogues of tiazofurin (TZF) with 2-[5,5-bis(hydroxymethyl)pyrrolidin-2-yl] moiety, as sugar mimic, were synthesized from O,O-cyclohexylidene derivative of 4,4-bis(hydroxymethyl)-4-nitrobutanal in multi-gram scale. The synthetic route consisted of three stages: (i) the synthesis of corresponding derivative of 5,5-bis(hydroxymethyl)pyrrolidine-2-carbonitrile, (ii) the construction of ethyl thiazole-2-carboxylate part by the conversion of the pyrrolidine-2-carbonitrile into the N-trifluoroacetyl derivative followed by cyclocondensation with L-cysteine ethyl ester and then by dehydrogenation, and (iii) the final transformation of the ethyl thiazole-4-carboxylate into the aza-analogues of TZF. The TZF aza-analogues were evaluated for their antiviral activities in cell-culture-based assays.


Assuntos
Compostos Aza/síntese química , Pirrolidinas/síntese química , Ribavirina/análogos & derivados , Animais , Antivirais/síntese química , Antivirais/farmacologia , Compostos Aza/farmacologia , Carboidratos/síntese química , Carboidratos/farmacologia , Chlorocebus aethiops , Cisteína/análogos & derivados , Cisteína/química , Vírus de DNA/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/virologia , Células HeLa , Humanos , Mimetismo Molecular , Pirrolidinas/farmacologia , Vírus de RNA/efeitos dos fármacos , Ribavirina/síntese química , Ribavirina/farmacologia , Células Vero
14.
Bioorg Med Chem ; 18(7): 2748-55, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20207546

RESUMO

Ribavirin is a nucleoside analogue with broad antiviral activity. Here we report the synthesis and biological evaluation of novel ribavirin ProTides designed to deliver the bioactive ribavirin monophosphate into cells. Some of the compounds display activity similar to the parent nucleoside against a range of viruses. Enzymatic, cell lysate and preliminary modeling studies have been performed to investigate the lack of enhancement of potency by the ProTides, and these indicate a failure at the final, amino acid cleavage step in the ProTide activation process, leading to inefficient release of the nucleoside monophosphate.


Assuntos
Antivirais/síntese química , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Pró-Fármacos/síntese química , Ribavirina/análogos & derivados , Ribavirina/síntese química , Amidas/síntese química , Amidas/farmacologia , Antivirais/farmacologia , Linhagem Celular , Efeito Citopatogênico Viral , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/síntese química , Peptídeos/farmacologia , Ácidos Fosfóricos/síntese química , Ácidos Fosfóricos/farmacologia , Pró-Fármacos/farmacologia , Ribavirina/farmacologia , Vírus/efeitos dos fármacos
16.
Clin Liver Dis ; 13(3): 391-401, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19628156

RESUMO

Hepatitis C virus (HCV) infection remains a large-scale and significant health concern. The combination of subcutaneously administered pegylated interferon and oral ribavirin is the FDA-approved regimen for the treatment of chronic HCV infection. Combination therapy may result in a sustained virologic response leading to HCV eradication, with a reduction in risk for cirrhosis, hepatic decompensation, and hepatocellular carcinoma. However, the combination of PEG-IFN and ribavirin does not universally result in cure in all patients who undergo treatment. In this article, the authors discuss immunomodulatory therapies and clinical trials in the treatment of HCV infection.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/imunologia , Hepatite C Crônica/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/terapia , Humanos , Imunoglobulinas/uso terapêutico , Imunoterapia , Interferons/uso terapêutico , Nitrocompostos , Ribavirina/análogos & derivados , Ribavirina/uso terapêutico , Tiazóis/uso terapêutico , Receptores Toll-Like/agonistas , Vacinas contra Hepatite Viral/uso terapêutico
17.
Bioorg Med Chem ; 17(15): 5656-64, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19596199

RESUMO

Diadenosine disulfide (5) was reported to inhibit NAD kinase from Listeria monocytogenes and the crystal structure of the enzyme-inhibitor complex has been solved. We have synthesized tiazofurin adenosine disulfide (4) and the disulfide 5, and found that these compounds were moderate inhibitors of human NAD kinase (IC(50)=110 microM and IC(50)=87 microM, respectively) and Mycobacterium tuberculosis NAD kinase (IC(50)=80 microM and IC(50)=45 microM, respectively). We also found that NAD mimics with a short disulfide (-S-S-) moiety were able to bind in the folded (compact) conformation but not in the common extended conformation, which requires the presence of a longer pyrophosphate (-O-P-O-P-O-) linkage. Since majority of NAD-dependent enzymes bind NAD in the extended conformation, selective inhibition of NAD kinases by disulfide analogues has been observed. Introduction of bromine at the C8 of the adenine ring restricted the adenosine moiety of diadenosine disulfides to the syn conformation making it even more compact. The 8-bromoadenosine adenosine disulfide (14) and its di(8-bromoadenosine) analogue (15) were found to be the most potent inhibitors of human (IC(50)=6 microM) and mycobacterium NAD kinase (IC(50)=14-19 microM reported so far. None of the disulfide analogues showed inhibition of lactate-, and inosine monophosphate-dehydrogenase (IMPDH), enzymes that bind NAD in the extended conformation.


Assuntos
Adenosina/química , Adenosina/farmacologia , Dissulfetos/química , Dissulfetos/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Ribavirina/análogos & derivados , Adenosina/síntese química , Sítios de Ligação , Dissulfetos/síntese química , Humanos , Modelos Moleculares , Conformação Molecular , Mycobacterium tuberculosis/enzimologia , NAD/análogos & derivados , Fosfotransferases (Aceptor do Grupo Álcool)/química , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Ribavirina/síntese química , Ribavirina/química , Ribavirina/farmacologia
18.
Carbohydr Res ; 344(11): 1270-5, 2009 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-19527904

RESUMO

A series of novel ribavirin hydrazone derivatives were synthesized by the reaction of ribavirin hydrazone with benzaldehyde or acetophenone derivatives. The structures of the compounds were determined by IR, (1)H NMR, and HRESIMS. Preliminary biological evaluation showed that one compound (7h) inhibits the growth of A549 cells at 20microM.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Hidrazonas/síntese química , Hidrazonas/farmacologia , Neoplasias Pulmonares/patologia , Ribavirina/análogos & derivados , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Hidrazonas/química
19.
Biochem Biophys Res Commun ; 375(3): 341-5, 2008 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-18706892

RESUMO

The eukaryotic translation initiation factor eIF4E is dysregulated in many cancers. eIF4E, through its mRNA export and translation functions, combinatorially modulates the expression of genes involved in Akt dependent survival signaling. For these activities, eIF4E must bind the 7-methyl guanosine (m(7)G) cap moiety on the 5'-end of mRNAs. We demonstrate that a physical mimic of the m(7)G cap, ribavirin, inhibits eIF4E dependent Akt survival signaling. Specifically, ribavirin impairs eIF4E mediated Akt activation via inhibiting the production of an upstream activator of Akt, NBS1. Consequently, ribavirin impairs eIF4E dependent apoptotic rescue. A ribavirin analog with distinct physico-chemical properties, tiazofurin, does not impair eIF4E activity indicating that only analogs that mimic the m(7)G cap will inhibit eIF4E function. Ribavirin represents a first-in-class strategy to inhibit eIF4E dependent cancers, through competition for m(7)G cap binding. Thus, ribavirin coordinately impairs eIF4E dependent pathways and thereby, potently inhibits its biological effects.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Fator de Iniciação 4E em Eucariotos/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ribavirina/farmacologia , Animais , Antivirais/farmacologia , Apoptose , Transporte Biológico/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Fator de Iniciação 4E em Eucariotos/metabolismo , Humanos , Camundongos , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Regulon/efeitos dos fármacos , Ribavirina/análogos & derivados
20.
J Neurol Sci ; 267(1-2): 76-85, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17996253

RESUMO

Experimental autoimmune encephalomyelitis (EAE) is an animal model of multiple sclerosis (MS) and the helpful tool in preclinical testing of various substances considered for treatment of this human CNS disease. Ribavirin (R) and tiazofurin (T) are purine nucleoside analogues, with the broad spectrum of anti-viral, anti-tumoral and anti-inflammatory properties. We proposed that combined treatment with RT, administrated during the effector phase of EAE, would attenuate disease severity, both clinically and pathologically. Ribavirin was given daily at a dosage of 30 mg/kg and tiazofurin was given at a dosage of 10 mg/kg every other day for 15 days. We detected amelioration of clinical signs and faster recovery in the RT group compared to the control group. Immunohistochemical analyses revealed that RT treatment decrease the number of T cells, macrophages and microglia. In the controls, we detected reactive type of microglia, while in the RT group we noticed ramified/resting form. Demyelination areas and axonal damage were not recorded in the RT group, in contrast to the control group where multiple areas of demyelination zones and axonal loss were found. RT combination treatment suppresses ongoing EAE, prevents demyelination and axonal loss, and therefore may well be the potential therapy for the treatment of MS.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Ribavirina/análogos & derivados , Ribavirina/farmacologia , Animais , Antimetabólitos Antineoplásicos/farmacologia , Antivirais/farmacologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/fisiopatologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/imunologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/fisiopatologia , Gliose/tratamento farmacológico , Gliose/imunologia , Gliose/fisiopatologia , Terapia de Imunossupressão/métodos , Masculino , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/imunologia , Bainha de Mielina/patologia , Ratos , Resultado do Tratamento , Degeneração Walleriana/tratamento farmacológico , Degeneração Walleriana/imunologia , Degeneração Walleriana/fisiopatologia
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