RESUMO
Despite the serious public health problem represented by the diseases caused by dengue (DENV), Zika (ZIKV) and chikungunya (CHIKV) viruses, there are still no specific licensed antivirals available for their treatment. Here, we examined the potential anti-arbovirus activity of ten di-halogenated compounds derived from L-tyrosine with modifications in amine and carboxyl groups. The activity of compounds on VERO cell line infection and the possible mechanism of action of the most promising compounds were evaluated. Finally, molecular docking between the compounds and viral and cellular proteins was evaluated in silico with Autodock Vina®, and the molecular dynamic with Gromacs®. Only two compounds (TDC-2M-ME and TDB-2M-ME) inhibited both ZIKV and CHIKV. Within the possible mechanism, in CHIKV, the two compounds decreased the number of genome copies and in the pre-treatment strategy the infectious viral particles. In the ZIKV model, only TDB-2M-ME inhibited the viral protein and demonstrate a virucidal effect. Moreover, in the U937 cell line infected with CHIKV, both compounds inhibited the viral protein and TDB-2M-ME inhibited the viral genome too. Finally, the in silico results showed a favorable binding energy between the compounds and the helicases of both viral models, the NSP3 of CHIKV and cellular proteins DDC and ß2 adrenoreceptor.
Assuntos
Antivirais/síntese química , Vírus Chikungunya/efeitos dos fármacos , Vírus da Dengue/efeitos dos fármacos , Fenóis/síntese química , Tirosina/análogos & derivados , Zika virus/efeitos dos fármacos , Animais , Antivirais/química , Antivirais/farmacologia , Linhagem Celular , Vírus Chikungunya/genética , Vírus Chikungunya/metabolismo , Chlorocebus aethiops , Vírus da Dengue/genética , Genoma Viral/efeitos dos fármacos , Halogenação , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Células Vero , Zika virus/genética , Zika virus/metabolismoRESUMO
Hepatitis C virus (HCV) affects about 170 million people worldwide. The current treatment has a high cost and variable response rates according to the virus genotype. Acridones, a group of compounds extracted from natural sources, showed potential antiviral actions against HCV. Thus, this study aimed to evaluate the effect of a panel of 14 synthetic acridones on the HCV life cycle. The compounds were screened using an Huh7.5 cell line stably harbouring the HCV genotype 2a subgenomic replicon SGR-Feo-JFH-1. Cells were incubated in the presence or absence of compounds for 72 h and cell viability and replication levels were assessed by MTT and luciferase assays, respectively. At a concentration of 5 µM the acridone Fac4 exhibited a >90â% inhibition of HCV replication with no effect on cell viability. The effects of Fac4 on virus replication, entry and release steps were evaluated in Huh7.5 cells infected with the JFH-1 isolate of HCV (HCVcc). Fac4 inhibited JFH-1 replication to approximately 70â%, while no effect was observed on virus entry. The antiviral activity of Fac4 was also observed on viral release, with almost 80â% of inhibition. No inhibitory effect was observed against genotype 3 replication. Fac4 was able to intercalate into dsRNA, however did not inhibit NS5B polymerase activity or translation driven by the HCV IRES. Although its mode of action is partly understood, Fac4 presents significant inhibition of HCV replication and can therefore be considered as a candidate for the development of a future anti-HCV treatment.
Assuntos
Acridonas/farmacologia , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Replicação Viral/efeitos dos fármacos , Acridonas/síntese química , Antivirais/síntese química , Genoma Viral/efeitos dos fármacos , Hepacivirus/genética , Hepatite C/virologia , Humanos , Replicon/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacosRESUMO
Dengue virus (DENV) is the most prevalent mosquito borne viral pathogen worldwide. In this work we first evaluated the antiviral activity of natural and synthetic ß-carbolines against DENV-2 multiplication in cell cultures. We determined that the natural ß-carboline harmol and a synthetic harmine derivative, 9N-methylharmine, exhibit inhibitory effect on DENV-2 production without virucidal activity. The active compounds were inhibitory of all DENV serotypes, being DENV-2 the more susceptible to their antiviral action. The mode of action of 9N-methylharmine against DENV-2 was further explored. We determined that the derivative neither affects viral adsorption-internalization events nor viral RNA synthesis. The quantification of intracellular and extracellular viral genomes and infectious virus particles indicated that 9N-methylharmine would impair the maturation and release of virus particles to the extracellular medium affecting the spreading of the infection. Furthermore, we also determined that 9N-methylharmine antiviral activity is not related to the ability of the compound to downregulate p38 MAPK phosphorylation.
Assuntos
Antivirais/farmacologia , Carbolinas/química , Carbolinas/farmacologia , Vírus da Dengue/efeitos dos fármacos , Animais , Carbolinas/síntese química , Chlorocebus aethiops , Vírus da Dengue/genética , Descoberta de Drogas , Genoma Viral/efeitos dos fármacos , Harmina/análogos & derivados , Harmina/química , Harmina/farmacologia , Humanos , Fosforilação/efeitos dos fármacos , RNA Viral/efeitos dos fármacos , Células Vero , Replicação Viral/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacosRESUMO
Dengue is the most common mosquito borne viral disease in humans. The infection with any of the 4 dengue virus serotypes (DENV) can either be asymptomatic or manifest in two clinical forms, the mild dengue fever or the more severe dengue hemorrhagic fever that may progress into dengue shock syndrome. A DENV replicative cycle relies on host lipid metabolism; specifically, DENV infection modulates cholesterol and fatty acid synthesis, generating a lipid-enriched cellular environment necessary for viral replication. Thus, the aim of this work was to evaluate the anti-DENV effect of the Nordihydroguaiaretic acid (NDGA), a hypolipidemic agent with antioxidant and anti-inflammatory properties. A dose-dependent inhibition in viral yield and NS1 secretion was observed in supernatants of infected cells treated for 24 and 48 h with different concentrations of NDGA. To evaluate the effect of NDGA in DENV replication, a DENV4 replicon transfected Vero cells were treated with different concentrations of NDGA. NDGA treatment significantly reduced DENV replication, reiterating the importance of lipids in viral replication. NDGA treatment also led to reduction in number of lipid droplets (LDs), the neutral lipid storage organelles involved in DENV morphogenesis that are known to increase in number during DENV infection. Furthermore, NDGA treatment resulted in dissociation of the C protein from LDs. Overall our results suggest that NDGA inhibits DENV infection by targeting genome replication and viral assembly.
Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Dengue/virologia , Masoprocol/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Linhagem Celular , Replicação do DNA/efeitos dos fármacos , Dengue/tratamento farmacológico , Vírus da Dengue/genética , Vírus da Dengue/crescimento & desenvolvimento , Vírus da Dengue/fisiologia , Genoma Viral/efeitos dos fármacos , Humanos , Proteínas Virais/genética , Proteínas Virais/metabolismo , Montagem de Vírus/efeitos dos fármacosAssuntos
Regiões 5' não Traduzidas/genética , Terapia Antirretroviral de Alta Atividade , Sequência Conservada , Genoma Viral/genética , Infecções por HIV/complicações , Hepacivirus/genética , Hepatite C Crônica/complicações , Adulto , Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Sequência de Bases , Feminino , Variação Genética , Genoma Viral/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Dados de Sequência MolecularRESUMO
BACKGROUND: Hepatitis C virus (HCV) is a major public health problem with 170 million chronically infected people throughout the world. Currently, the only treatment available consists of a combination of pegylated interferon (INF-alpha) and ribavirin, but only half of the patients treated show a sufficient antiviral response. Thus there is a great need for the development of new treatments for HCV infections. RNA interference (RNAi) represents a new promising approach to develop effective antiviral drugs and has been extremely effective against HCV gene expression in short-term cell culture. Our aim was to determine the effect of RNAi directed against the NS5B-HCV region on HCV expression in a human hepatoma cell line that expresses HCV-subgenomic replicon (Huh7 HCV replicon cells). METHODS: We transfected Huh7 HCV replicon cells with different concentrations of RNAi (100-200 nM) targeting the NS5B region of the viral genome. 2-6 days post-transfection HCV-RNA was quantified by semiquantitative and real-time RT-PCR, and HCV NS5B protein levels were assayed by western blot. Cell viability was also quantified by MTT assay. RESULTS: Our results indicate that the NS5B-siRNAs used in this study can specifically inhibit HCV-RNA replication and protein expression (more than 90%) compared to control cells. CONCLUSIONS: Synthetic siRNA against NS5BHCV inhibited HCV replication and viral proteins levels and thereby becomes a powerful strategy to combat hepatitis C virus.