RESUMO
Potato virus Y (PVY) is a highly destructive pathogen that infects Solanum tuberosumvL., commonly known as potato, a crop that produces one of the most crucial food staples of the world. The PVY viral infection can considerably reduce the yield and quality of potatoes, thereby causing significant economic ramifications. Given the unsatisfactory performance of commercially available antiviral agents against PVY, we synthesized a series of novel indole-derived compounds followed by their bioevaluation and investigation of the mechanisms governing their anti-PVY activity. These indole-based derivatives contain dithioacetal as a key chemical moiety, and most of them exhibit promising anti-PVY activities. In particular, compound B2 displays remarkable in vivo protective and inactivating properties, with half-maximal effective concentration (EC50) values of 209.3 and 113.0 µg/mL, respectively, in stark contrast to commercial agents such as ningnanmycin (EC50 = 281.4 and 136.3 µg/mL, respectively) and ribavirin (EC50 = 744.8 and 655.4 µg/mL, respectively). The mechanism using which B2 enhances plant immune response to protect plants from PVY is elucidated using enzyme activity tests, real-time quantitative polymerase chain reaction (RT-qPCR), and proteomics techniques. This study aims to pave the way for developing candidate pesticides and related molecules using antiphytoviral activity.
Assuntos
Potyvirus , Solanum tuberosum , Indóis/farmacologia , Antivirais/farmacologia , Antivirais/química , Ribavirina/farmacologia , Doenças das Plantas/prevenção & controleRESUMO
In this study, methods of Actinidia chlorotic ringspot-associated virus (AcCRaV) elimination by shoot tip culture, thermotherapy followed by shoot tip culture, and chemotherapy followed by shoot tip culture were explored. The results showed that the AcCRaV elimination rate was 23.3% when the secondary shoot tip culture method was used and when the shoot tip length was less than 0.5 mm. The AcCRaV elimination rate was 100% when thermotherapy (36°C [day] and 32°C [night]) was applied for 20 days followed by shoot tip culture (shoot tip length less than 1.0 mm). When shoot segments were treated with ribavirin at 15 µg/ml for 2 months followed by shoot tip culture, the elimination rate of AcCRaV was 100% (shoot tip length less than 1.0 mm). When shoot segments were treated with ribavirin at 25 µg/ml for 2 months followed by shoot tip culture, the elimination rate of AcCRaV was 100% (shoot tip length less than 1.5 mm). This is the first report on kiwifruit virus elimination methods.
Assuntos
Actinidia , Vírus , Ribavirina/farmacologia , Brotos de Planta , FrutasRESUMO
BACKGROUND: Traditional Chinese medicine Yinhuapinggan granule (YHPG) has been used for treating upper respiratory tract infection like influenza, cough, and viral pneumonia. However, its active ingredients that really exert the main efficacy have not been well elucidated. This study is aimed at screening its antiviral components and investigating the potential therapeutic mechanisms of YHPG against the influenza A/PR8/34 (H1N1) virus in Madin Darby canine kidney (MDCK). METHODS: MDCK cells were infected with the influenza virus and then treated with ribavirin, YHPG, and main active ingredients in YHPG. Based on the maximum nontoxic concentration (TC0), half-maximal toxic concentration (TC50), half-maximal inhibitory concentration (IC50), and therapeutic index (TI), interferon-ß (IFN-ß) and interleukin-6 (IL-6) levels were measured using enzyme-linked immunosorbent assay (ELISA), and the gene expression of TLR7, MyD88, tumor necrosis factor receptor-associated factor 6 (TRAF6), c-Jun amino terminal kinase (JNK), p38 mitogen-activated protein kinase (p38 MAPK), and p65 nuclear transcription factor-kappa B (p65 NF-κB) was quantified using reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The results indicated that the components of YHPG, such as ephedrine hydrochloride, pseudoephedrine hydrochloride, chlorogenic acid, and emodin, had significant antiviral effects. High and medium doses of YHPG effectively reduced the cytopathic effect (CPE) and significantly decreased IFN-ß and IL-6 levels in the supernatant. Simultaneously, the transcript levels of TLR7, MyD88, TRAF6, JNK, p38 MAPK, and p65 NF-κB decreased in infected MDCK cells. Moreover, a certain dose-dependent relationship among different groups of YHPG was observed. CONCLUSIONS: These results indicated that YHPG and the components of YHPG had a significant inhibitory function on the proliferation of the H1N1 virus. The mechanism might be associated with suppressing the activation of the TLR7/MyD88 signaling pathway, a decrease in the mRNA expression of key target genes, and inhibition of IFN-ß and IL-6 secretion.
Assuntos
Antivirais/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Animais , Cães , Interferon beta/metabolismo , Interleucina-6/metabolismo , Dose Letal Mediana , Células Madin Darby de Rim Canino , Medicina Tradicional Chinesa , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Ribavirina/farmacologia , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 7 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismoRESUMO
BACKGROUND: Current therapy of chronic hepatitis C virus (HCV) with direct-acting antivirals (DAAs) has dramatically improved the sustained virologic response (SVR) of affected patients; however, treatment with DAAs remains expensive, and drug-resistant HCV variants remain a threat. As a result, there is still a need to continue to develop affordable and effective drugs for the treatment of HCV. Previously, we have demonstrated that a crude extract from Artocarpus heterophyllus leaves is a potential anti-HCV candidate. In this study, we have further purified this crude extract, examined which sub-fraction possesses the highest antiviral activity, and then explored its efficacy at different HCV life cycle stages. We also assessed synergistic antiviral effects between the A. heterophyllus extract and commercially available anti-HCV drugs. METHODS: We used vacuum liquid chromatography (VLC) and high-performance liquid chromatography (HPLC) to fractionate a dichloromethane extract of A. heterophyllus leaves. We then examined the anti-HCV activity of the fractions using HCV genotype 2a, JFH1a; the antiviral mode of action was determined by exploring adding the treatments at different times. We examined the antiviral effects on the viral entry stage through a virucidal activity test, viral adsorption examination, and pretreatment of cells with the drug. The effects on the post-viral entry stage were determined by the levels of HCV protein expression and HCV RNA expression in infected cells. RESULTS: Through activity guided purification, we identified the sub-fraction FR3T3 as possessing the most robust anti-HCV activity with an IC50 value of 4.7 ± 1.0 µg/mL. Mode-of-action analysis revealed that FR3T3 inhibited post-viral entry stages such as HCV NS3 protein expression and HCV RNA replication with marginal effects on the viral entry stage. Thin-layer Chromatography (TLC) indicated that FR3T3 contained terpenoids and chlorophyll-related compounds. We also found a synergistic antiviral activity when the DCM extract of A. heterohyllus was used in combination therapy with commercial anti-HCV drugs; Ribavirin, Simeprevir, Cyclosporin A. CONCLUSIONS: The extract of A. heterophyllus and its sub-fraction, FR3T3, presented here have anti-HCV activities and could be candidate drugs for add-on-therapy for treatment of chronic HCV infections.
Assuntos
Antivirais/farmacologia , Hepatite C Crônica/tratamento farmacológico , Extratos Vegetais/farmacologia , Artocarpus , Linhagem Celular , Ciclosporina/farmacologia , Quimioterapia Combinada , Humanos , Indonésia , Oligopeptídeos/farmacologia , Folhas de Planta , Ribavirina/farmacologiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: According to the theory of traditional Chinese medicine, the main pathogenesis of severe hand, foot and mouth disease (HFMD) is that the heat and wet poisons are deeply trapped in the viscera, which causes the deficiency of Qi and Yin in the patient's body. Ginsenoside Rb1 (Rb1) is the most abundant triterpenoid saponin in Panax quinquefolius L., which has the function of Qi-invigorating and Yin-nourishing. Enterovirus 71 (EV71) is one of the causative pathogens of HFMD, especially the form associated with some lethal complications. Therefore, the therapeutic effect of Rb1 on this disease caused by EV71 infection is worth exploring. AIM OF THE STUDY: We explored the effective antiviral activities of Rb1 against EV71 in vitro and in vivo and investigated its preliminary antiviral mechanisms. MATERIAL AND METHODS: EV71-infected two-day-old suckling mice model was employed to detect the antiviral effects of Rb1 in vivo. To detect the antiviral effects of Rb1 in vitro, cytopathic effect (CPE) reduction assay was performed in EV71-infected Rhabdomyosarcoma (RD) cells. Interferon (IFN)-ß interference experiment was employed to detect the antiviral mechanism of Rb1. RESULTS: In this paper, we first found that Rb1 exhibited strong antiviral activities in EV71-infected suckling mice when compared to those of ribavirin. Administration of Rb1 reduced the CPE of EV71-infected RD cells in a dose-dependent manner. Moreover, EV71-induced viral protein-1 (VP-1) expression was significantly reduced by Rb1 administration in vitro and in vivo. Furthermore, Rb1 treatment could induce high cellular and humoral immune responses in vivo. Meanwhile, Rb1 contributed to the enhanced Type I IFN responses and IFN-ß knockdown reversed the antiviral activity of Rb1 in vitro. CONCLUSION: In summary, our findings suggest that Rb1 is an immune-stimulatory agent and provide an insight into therapeutic potentials of Rb1 for the treatment of EV71 infection.
Assuntos
Antivirais/farmacologia , Enterovirus Humano A/efeitos dos fármacos , Infecções por Enterovirus/tratamento farmacológico , Ginsenosídeos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Antivirais/administração & dosagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Infecções por Enterovirus/virologia , Ginsenosídeos/administração & dosagem , Humanos , Camundongos , Camundongos Endogâmicos ICR , Panax/química , Rabdomiossarcoma/virologia , Ribavirina/farmacologiaRESUMO
Recombinant viruses expressing fluorescent or luminescent reporter proteins are used to quantitate and visualize viral replication and transmission. Here, we used a split NanoLuc luciferase (NLuc) system comprising large LgBiT and small HiBiT peptide fragments to generate stable reporter rotaviruses (RVs). Reporter RVs expressing NSP1-HiBiT fusion protein were generated by placing an 11 amino acid HiBiT peptide tag at the C-terminus of the intact simian RV NSP1 open reading frame or truncated human RV NSP1 open reading frame. Virus-infected cell lysates exhibited NLuc activity that paralleled virus replication. The antiviral activity of neutralizing antibodies and antiviral reagents against the recombinant HiBiT reporter viruses were monitored by measuring reductions in NLuc expression. These findings demonstrate that the HiBiT reporter RV systems are powerful tools for studying the viral life cycle and pathogenesis, and a robust platform for developing novel antiviral drugs.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Genes Reporter , Luciferases/genética , Peptídeos/genética , Rotavirus/genética , Animais , Antivirais/farmacologia , Cricetinae , Humanos , Camundongos , Microrganismos Geneticamente Modificados , Testes de Neutralização , Ribavirina/farmacologia , Rotavirus/fisiologia , Infecções por Rotavirus/tratamento farmacológico , Infecções por Rotavirus/virologia , Proteínas não Estruturais Virais/genética , Replicação Viral/genéticaRESUMO
The computational search of chemical libraries has been used as a powerful tool for the rapid discovery of candidate compounds. To find small molecules with anti-feline infectious peritonitis virus (FIPV) properties, we utilized a virtual screening technique to identify the active site on the viral protease for the binding of the available natural compounds. The protease 3CL (3CLpro) plays an important role in the replication cycle of FIPV and other viruses within the family Coronaviridae. The 15 best-ranked candidate consensus compounds, based on three docking tools, were evaluated for further assays. The protease inhibitor assay on recombinant FIPV 3CLpro was performed to screen the inhibitory effect of the candidate compounds with IC50 ranging from 6.36 ± 2.15 to 78.40 ± 2.60 µM. As determined by the cell-based assay, the compounds NSC345647, NSC87511, and NSC343256 showed better EC50 values than the broad-spectrum antiviral drug ribavirin and the protease inhibitor lopinavir, under all the test conditions including pre-viral entry, post-viral entry, and prophylactic activity. The NSC87511 particularly yielded the best selective index (>4; range of SI = 13.80-22.90). These results indicated that the natural small-molecular compounds specifically targeted the 3CLpro of FIPV and inhibited its replication. Structural modification of these compounds may generate a higher anti-viral potency for the further development of a novel therapy against FIP.
Assuntos
Antivirais/química , Coronavirus Felino/enzimologia , Peritonite Infecciosa Felina/virologia , Peptídeo Hidrolases/química , Inibidores de Proteases/química , Proteínas Virais/química , Animais , Antivirais/farmacologia , Domínio Catalítico , Gatos , Simulação por Computador , Coronavirus Felino/química , Coronavirus Felino/efeitos dos fármacos , Coronavirus Felino/genética , Avaliação Pré-Clínica de Medicamentos , Cinética , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Inibidores de Proteases/farmacologia , Ribavirina/química , Ribavirina/farmacologia , Proteínas Virais/genética , Proteínas Virais/metabolismoRESUMO
Scutellaria baicalensis Georgi has been widely used in China for treatment of various diseases. This study investigated the effect of Scutellaria baicalensis Georgi extracts (SBE) against Coxsackievirus B3 (CVB3)-induced myocarditis in vitro and in vivo. In vitro, Hela cells and primary myocardial cells were infected with CVB3 and treated with SBE (50-800 µg/ml) and ribavirin (200 µM) for 48 h and then determined by CCK8 assay. Real-time PCR and western blotting assays were performed. In vivo, a myocarditis model was induced in male BALB/c mice by injecting CVB3 suspension intraperitoneally for three times, followed by treatment with SBE (400 and 200 mg/kg) and ribavirin (100 mg/kg) for 28 days. SBE ameliorated the cytotoxicity of CVB3 in Hela cells, especially at 400 µg/ml (39.93% vs 65.67%, p < 0.05) without influencing cell growth and also significantly reduced CVB3 replication in primary myocardial cells. The levels of AKT, ERK, and p38 were increased after CVB3 infection. SBE could downregulate the expressions of AKT and p38. In vivo, the mortality rate from CVB3 reached to 66.67%, while 10.00% and 23.33% of this came after 400 and 200 mg/kg SBE treatment, respectively (p < 0.05). The CVB3 replication was obviously reduced after SBE administration from day 5. Similarly, the levels of AKT, ERK, and p38 mRNAs and proteins were increased, and SBE suppressed the expression of AKT and p38. Our study indicates that SBE is a promising potent antiviral agent against CVB3-induced myocarditis by inhibition of virus replication via depressing AKT and p38 expressions.
Assuntos
Antivirais/farmacologia , Infecções por Coxsackievirus/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Miocardite/tratamento farmacológico , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Scutellaria baicalensis/química , Animais , Modelos Animais de Doenças , Enterovirus/patogenicidade , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Miocardite/patologia , Ribavirina/farmacologia , Replicação Viral/efeitos dos fármacosRESUMO
The use of antifungal agents in clinical settings is limited by the appearance of drug resistance and adverse side effects. There is, therefore, an urgent need to develop new drugs to strengthen the treatment of invasive fungal diseases. The aim of this study is to describe the potential repurposing of ribavirin as an adjunct therapy against Candida spp. Primary screening of a Prestwick Chemical library against Candida albicans ATCC 90028 and fluconazole-resistant Candida albicans strains was performed. Subsequently, we evaluated the responses of 100 Candida sp. strains to ribavirin, an antiviral agent, using the broth microdilution method as recommended by CLSI. We checked the involvement of efflux pump activity in the development of ribavirin resistance. We studied time-kill curves and performed a checkerboard assay for a ribavirin-antifungal combination study. Twenty-one nonstandard antifungal compounds were identified, including ribavirin. Ribavirin had antifungal activity in vitro against 63 Candida strains, including strains of C. albicans, C. parapsilosis, and C. tropicalis, with MICs ranging from 0.37 to 3.02 µg/ml, while MICs for C. krusei, C. glabrata, C. lusitaniae, and some C. albicans strains remained high (≥24.16 µg/ml). No relation was observed between efflux pump activity and ribavirin resistance. Ribavirin exhibited fungistatic activity against multidrug-resistant (MDR) C. albicans and fungicidal activity against a C. parapsilosis strain. In addition, ribavirin acted synergistically with azoles against Candida strains for which ribavirin MICs were <24.4 µg/ml. This study highlights the potential clinical application of ribavirin, alone or in association with other antifungal agents, as an adjunct anti-Candida drug.
Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida parapsilosis/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Reposicionamento de Medicamentos , Farmacorresistência Fúngica/efeitos dos fármacos , Ribavirina/farmacologia , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida parapsilosis/genética , Candida parapsilosis/crescimento & desenvolvimento , Candida tropicalis/genética , Candida tropicalis/crescimento & desenvolvimento , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/microbiologia , Sinergismo Farmacológico , Fluconazol/farmacologia , Expressão Gênica , Genes MDR , Humanos , Testes de Sensibilidade Microbiana , Medicamentos sob Prescrição/farmacologia , Triazóis/farmacologiaRESUMO
Bovine viral diarrhea virus (BVDV) fall into cytopathic (CP) and noncytopathic (NCP) biotypes, based on their ability to kill cultured cells. NCP-BVDV can not be titrated by conventional means as used for CP-BVDV, which has impeded the identification of antiviral drugs targeting NCP-BVDV virus strains. In this study, the application of an immunoperoxidase assay in the screening of antiviral drugs was tested using two known BVDV inhibitors, ribavirin and ammonium chloride (NH4Cl). Phospholipase C inhibitor U73122 was identified to affect BVDV infection by using this immunoperoxidase assay. In addition, the results of immunoperoxidase assay were validated by real-time PCR. Taken together, the immunoperoxidase assay is a useful and versatile method suitable for antiviral drug screening targeting NCP-BVDV.
Assuntos
Antivirais/farmacologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/tratamento farmacológico , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Técnicas Imunoenzimáticas/métodos , Cloreto de Amônio/farmacologia , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Efeito Citopatogênico Viral/efeitos dos fármacos , Vírus da Diarreia Viral Bovina/fisiologia , Estrenos/farmacologia , Técnicas Imunoenzimáticas/normas , Pirrolidinonas/farmacologia , Ribavirina/farmacologia , Replicação Viral/efeitos dos fármacosRESUMO
Lassa virus (LASV), a mammarenavirus, infects an estimated 100,000â»300,000 individuals yearly in western Africa and frequently causes lethal disease. Currently, no LASV-specific antivirals or vaccines are commercially available for prevention or treatment of Lassa fever, the disease caused by LASV. The development of medical countermeasure screening platforms is a crucial step to yield licensable products. Using reverse genetics, we generated a recombinant wild-type LASV (rLASV-WT) and a modified version thereof encoding a cleavable green fluorescent protein (GFP) as a reporter for rapid and quantitative detection of infection (rLASV-GFP). Both rLASV-WT and wild-type LASV exhibited similar growth kinetics in cultured cells, whereas growth of rLASV-GFP was slightly impaired. GFP reporter expression by rLASV-GFP remained stable over several serial passages in Vero cells. Using two well-characterized broad-spectrum antivirals known to inhibit LASV infection, favipiravir and ribavirin, we demonstrate that rLASV-GFP is a suitable screening tool for the identification of LASV infection inhibitors. Building on these findings, we established a rLASV-GFP-based high-throughput drug discovery screen and an rLASV-GFP-based antibody neutralization assay. Both platforms, now available as a standard tool at the IRF-Frederick (an international resource), will accelerate anti-LASV medical countermeasure discovery and reduce costs of antiviral screens in maximum containment laboratories.
Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Genes Reporter , Proteínas de Fluorescência Verde/análise , Vírus Lassa/crescimento & desenvolvimento , Substâncias Luminescentes/análise , Testes de Neutralização/métodos , Coloração e Rotulagem/métodos , Animais , Anticorpos Neutralizantes/imunologia , Antivirais/farmacologia , Chlorocebus aethiops , Fluorometria/métodos , Instabilidade Genômica , Proteínas de Fluorescência Verde/genética , Vírus Lassa/efeitos dos fármacos , Vírus Lassa/genética , Vírus Lassa/imunologia , Genética Reversa , Ribavirina/farmacologia , Células VeroRESUMO
INTRODUCTION: Ribavirin (RBV) is a broad-spectrum antiviral drug. Selenium nanoparticles (SeNPs) attract much attention in the biomedical field and are used as carriers of drugs in current research studies. In this study, SeNPs were decorated by RBV, and the novel nanoparticle system was well characterized. Madin-Darby Canine Kidney cells were infected with H1N1 influenza virus before treatment with RBV, SeNPs, and SeNPs loaded with RBV (Se@RBV). METHODS AND RESULTS: MTT assay showed that Se@RBV nanoparticles protect cells during H1N1 infection in vitro. Se@RBV depressed virus titer in the culture supernatant. Intracellular localization detection revealed that Se@RBV accumulated in lysosome and escaped to cytoplasm as time elapsed. Furthermore, activation of caspase-3 was resisted by Se@RBV. Expressions of proteins related to caspase-3, including cleaved poly-ADP-ribose polymerase, caspase-8, and Bax, were downregulated evidently after treatment with Se@RBV compared with the untreated infection group. In addition, phosphorylations of phosphorylated 38 (p38), JNK, and phosphorylated 53 (p53) were inhibited as well. In vivo experiments indicated that Se@RBV was found to prevent lung injury in H1N1-infected mice through hematoxylin and eosin staining. Tunel test of lung tissues present that DNA damage reached a high level but reduced substantially when treated with Se@RBV. Immunohistochemical test revealed an identical result with the in vitro experiment that activations of caspase-3 and proteins on the apoptosis pathway were restrained by Se@RBV treatment. CONCLUSION: Taken together, this study elaborates that Se@RBV is a novel promising agent against H1N1 influenza virus infection.
Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Nanopartículas/química , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Ribavirina/uso terapêutico , Selênio/uso terapêutico , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Cães , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Ribavirina/farmacologia , Selênio/farmacologia , Transdução de Sinais/efeitos dos fármacosRESUMO
Although preventable by vaccination, Measles still causes thousands of deaths among young children worldwide. The discovery of new antivirals is a good approach to control new outbreaks that cause such death. In this study, we tested the antiviral activity against Measles virus (MeV) of Polyphenol-rich extracts (PPs) coming from five seaweeds collected and cultivated in Mexico. An MTT assay was performed to determine cytotoxicity effect, and antiviral activity was measured by syncytia reduction assay and confirmed by qPCR. PPs from Ecklonia arborea (formerly Eisenia arborea, Phaeophyceae) and Solieria filiformis (Rhodophyta) showed the highest Selectivity Index (SI), >3750 and >576.9 respectively. Both PPs extracts were selected to the subsequent experiments owing to their high efficacy and low cytotoxicity compared with ribavirin (SI of 11.57). The combinational effect of PPs with sulphated polysaccharides (SPs) and ribavirin were calculated by using Compusyn software. Synergistic activity was observed by combining both PPs with low concentrations of Solieria filiformis SPs (0.01 µg/mL). The antiviral activity of the best combinations was confirmed by qPCR. Virucidal assay, time of addition, and viral penetration evaluations suggested that PPs act mainly by inactivating the viral particle. To our knowledge, this is the first report of the virucidal effect of Polyphenol-rich extracts of seaweeds.
Assuntos
Antivirais/farmacologia , Sinergismo Farmacológico , Vírus do Sarampo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Alga Marinha/química , Animais , Antivirais/isolamento & purificação , Antivirais/toxicidade , Chlorocebus aethiops , México , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Polifenóis/isolamento & purificação , Polifenóis/toxicidade , Polissacarídeos/farmacologia , Ribavirina/farmacologia , Células VeroRESUMO
Alphavirus non-structural protein, nsP1â¯has a distinct molecular mechanism of capping the viral RNAs than the conventional capping mechanism of host. Thus, alphavirus capping enzyme nsP1 is a potential drug target. nsP1 catalyzes the methylation of guanosine triphosphate (GTP) by transferring the methyl group from S-adenosylmethionine (SAM) to a GTP molecule at its N7 position with the help of nsP1 methyltransferase (MTase) followed by guanylylation (GT) reaction which involves the formation of m7GMP-nsP1 covalent complex by nsP1 guanylyltransferase (GTase). In subsequent reactions, m7GMP moiety is added to the 5' end of the viral ppRNA by nsP1 GTase resulting in the formation of cap0 structure. In the present study, chikungunya virus (CHIKV) nsP1 MTase and GT reactions were confirmed by an indirect non-radioactive colorimetric assay and western blot assay using an antibody specific for the m7G cap, respectively. The purified recombinant CHIKV nsP1â¯has been used for the development of a rapid and sensitive non-radioactive enzyme linked immunosorbent assay (ELISA) to identify the inhibitors of CHIKV nsP1. The MTase reaction is followed by GT reaction and resulted in m7GMP-nsP1 covalent complex formation. The developed ELISA nsP1 assay measures this m7GMP-nsP1 complex by utilizing anti-m7G cap monoclonal antibody. The mutation of a conserved residue Asp63 to Ala revealed its role in nsP1 enzyme reaction. Inductively coupled plasma mass spectroscopy (ICP-MS) was used to determine the presence of magnesium ions (Mg2+) in the purified nsP1 protein. The divalent metal ion selectivity and investigation show preference for Mg2+ ion by CHIKV nsP1. Additionally, using the developed ELISA nsP1 assay, the inhibitory effects of sinefungin, aurintricarboxylic acid (ATA) and ribavirin were determined and the IC50 values were estimated to be 2.69 µM, 5.72 µM and 1.18â¯mM, respectively.
Assuntos
Antivirais/farmacologia , Vírus Chikungunya/enzimologia , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática/métodos , Metiltransferases/antagonistas & inibidores , Proteínas Virais/antagonistas & inibidores , Adenosina/análogos & derivados , Adenosina/farmacologia , Ácido Aurintricarboxílico/farmacologia , Cátions Bivalentes/metabolismo , Coenzimas/metabolismo , Concentração Inibidora 50 , Magnésio/metabolismo , Ribavirina/farmacologiaRESUMO
Hepatitis C virus (HCV) treatment is aiming to cure and prevent the development, progression of fibrosis, and related complications. Interferon-based therapy was claimed to reduce or even reverse fibrosis. Although direct-acting agents have a better cure rate, we still lack the knowledge of their effect on fibrosis regression. We aim to assess fibrosis regression in direct-acting agents compared with interferon-based treatment regimens in the treatment of chronic HCV patients. The 204 chronic HCV patients were divided into 3 groups; group 1(N = 68) received Peg-IFN and ribavirin, group 2 (N = 69) received sofosbuvir and ribavirin, and group 3 (N = 67) received Peg-IFN, ribavirin, and sofosbuvir. Fibrosis assessment was performed by transient elastography (TE), APRI and FIB 4, in the pretreatment and at least 3 months after end of treatment. Of these, 66.2% of the patients did not show significant fibrosis changes, 6.4% fibrosis progressed, and 27.5% of fibrosis regressed (P < 0.0001) by TE. Similar results were detected in the different treatment regimens with no statistically significant difference between the regimens. Fibrosis regression was detected in 43.3% of cirrhotic patients who achieved sustained virological response (SVR) and only in 27.4% with significant fibrosis. Significant improvement of posttreatment aspartate transaminase, alanine transaminase, and alpha fetoprotein as well as APRI and FIB 4 scores were detected. Fibrosis regression (TE, APRI and FIB 4) was detected with direct-acting agents and interferon-based therapy. Treated patients with significant fibrosis will benefit of fibrosis regression irrespective to their treatment response, whereas fibrosis regression was associated with SVR in cirrhotic patients.
Assuntos
Antivirais/farmacologia , Fibrose/tratamento farmacológico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/farmacologia , Ribavirina/farmacologia , Sofosbuvir/farmacologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-IdadeRESUMO
The aim of this study was to retrospectively analyze the outcome of an unscheduled change in national Egyptian policies for the treatment of hepatitis C virus (HCV), which was transpired as a result of a reduction in interferon supplies, and to manage patients who already started interferon-based therapy. After completing a priming 4-weeks course of sofosbuvir/pegylated interferon/ribavirin (SOF/PEG IFN/RBV), a 12-weeks course of sofosbuvir/daclatasvir (SOF/DCV) combination was initiated. We evaluated the sustained virologic response at 12 weeks posttreatment (SVR12) for 2 groups of patients; Group 1, which included patients who had the previous regimen with IFN priming, and group 2, which included the first consecutive group of patients who received SOF/DCV for 12 weeks from the start without IFN priming. All group 1 patients (1,214 patients) achieved SVR12 (100%) and this was statistically significant when compared with the overall SVR12 in group 2 [8,869 patients with sustained virologic response [SVR] of 98.9%] (P value <0.001). No serious adverse events were reported in both groups. In this real-life treatment experience, interferon-based directly acting antiviral treatment with SOF/PEG IFN/RBV as a priming for 4 weeks, followed by SOF/DCV combination for 12 weeks, led to HCV viral suppression in all treated patients.
Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Imidazóis/farmacologia , Interferon-alfa/farmacologia , Ribavirina/farmacologia , Sofosbuvir/farmacologia , Carbamatos , Egito , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pirrolidinas , Estudos Retrospectivos , Valina/análogos & derivadosRESUMO
BACKGROUND: Although a contributory role of vitamin D levels for the development of chronic hepatitis C has been suggested, the efficacy of vitamin D supplementation in combination with conventional antiviral therapy consisting of pegylated interferon-α (Peg-IFN-α) injection and oral ribavirin (RBV) remains unclear. We investigated its efficacy in the treatment of chronic hepatitis C via a meta-analysis of randomised controlled trials. METHODS: We searched PubMed, EMBASE, the Cochrane Library, ClinicalTrials.gov and the bibliographies of relevant articles to locate additional publications in September 2016. Three evaluators independently reviewed and selected eligible studies based on predetermined selection criteria. RESULTS: Of 522 articles meeting our initial criteria, a total of seven open-label, randomised controlled trials involving 548 participants, were included in the final analysis. Vitamin D supplementation in combination with Peg-IFN-α injection and oral RBV significantly increased the rate of viral response for hepatitis C at 24 weeks after treatment in a random-effects meta-analysis (relative risk = 1.30; 95% confidence interval = 1.04-1.62; I2 = 75.9%). Also, its significant efficacy was observed in patients with hepatitis C virus genotype 1, which is known to be refractory to antiviral therapy. CONCLUSIONS: In summary, we observed that additional use of vitamin D has a positive effect on sustained viral response rates of patients with chronic hepatitis C infection. However, we cannot establish the efficacy because of substantial heterogeneity, a small sample size and a low methodological quality.
Assuntos
Antivirais/uso terapêutico , Suplementos Nutricionais , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Adulto , Idoso , Antivirais/farmacologia , Criança , Feminino , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Vitamina D/farmacologia , Vitaminas/farmacologiaRESUMO
Growing resistance in malarial parasites, particularly in Plasmodium falciparum needs a serious search for the discovery of novel drug targets. Inosine monophosphate dehydrogenase (IMPDH) is an important target for antimalarial drug discovery process in P. falciparum for the treatment of malaria. In the absence of x-ray crystal structure of this enzyme, homology modeling proved to be a reasonable alternate to study substrate binding mechanisms of this enzyme. In this study, a 3-D homology model for P. falciparum IMPDH was constructed taking human IMPDH (PDB code 1NF7) as template. Furthermore, an in-silico combinatorial library of ribavirin (RVP) derivatives (1347 molecules) was designed and virtually screened for ligands having selectively greater binding affinity with Plasmodium falciparum IMPDH relative to human IMPDH II. A total of five Ribavirin derivatives were identified as having greater binding affinity (-126 to -108Kcal/mol and -9.4 to -8.6Kcal/mol) with Plasmodium falciparum IMPDH. These five inhibitors should be used as selective and potent for Plasmodium falciparum IMPDH. Such type of study will provide information to synthetic medicinal chemist to enhance the potential of compounds (RVP derivatives) as chemotherapeutic agents to fight against the increasing burden of malarial infections.
Assuntos
Simulação por Computador , IMP Desidrogenase/antagonistas & inibidores , IMP Desidrogenase/química , Simulação de Acoplamento Molecular , Plasmodium falciparum/enzimologia , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , IMP Desidrogenase/metabolismo , Estrutura Molecular , Ribavirina/análogos & derivados , Ribavirina/química , Ribavirina/farmacologia , Relação Estrutura-AtividadeRESUMO
The "gold standard" treatment of patients with spinal root injuries consists of delayed surgical reconnection of nerves. The sooner, the better, but problems such as injury-induced motor neuronal death and muscle atrophy due to long-term denervation mean that normal movement is not restored. Herein we describe a preclinical model of root avulsion with delayed reimplantation of lumbar roots that was used to establish a new adjuvant pharmacological treatment. Chronic treatment (up to 6 months) with NeuroHeal, a new combination drug therapy identified using a systems biology approach, exerted long-lasting neuroprotection, reduced gliosis and matrix proteoglycan content, accelerated nerve regeneration by activating the AKT pathway, promoted the formation of functional neuromuscular junctions, and reduced denervation-induced muscular atrophy. Thus, NeuroHeal is a promising treatment for spinal nerve root injuries and axonal regeneration after trauma.
Assuntos
Acamprosato/farmacologia , Atrofia Muscular/tratamento farmacológico , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Radiculopatia/tratamento farmacológico , Ribavirina/farmacologia , Raízes Nervosas Espinhais/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Combinação de Medicamentos , Feminino , Vértebras Lombares , Denervação Muscular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Músculo Esquelético/cirurgia , Atrofia Muscular/fisiopatologia , Regeneração Nervosa/fisiologia , Radiculopatia/fisiopatologia , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Reimplante , Raízes Nervosas Espinhais/fisiopatologia , Raízes Nervosas Espinhais/cirurgiaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Mahuang-Xixin-Fuzi Decoction (MXF) as a famous formula for the treatment of colds, fever, nasal congestion and headache with elder people, has always been widely used in traditional Chinese medicine. The present study is aimed at investigating the treatment effect of MXF on Kidney-Yang deficiency syndrome in mice simultaneously infected with H1N1 virus. MATERIALS AND METHODS: We employed the Kidney-Yang deficiency mouse model to investigate the effect of MXF against influenza A virus (A/FM/1/47, H1N1). Mice were infected with the virus after fifteen days Kidney-Yang deficiency syndrome was established (intraperitoneal injection of estradiol benzoate), while MXF was orally administrated with 1.2-4.7g/kg/d for 6 consecutive days after inoculation. Body weight, rectal temperature, morbidity, and mortality were recorded daily. Histopathologic changes, antioxidant activity of SOD and MDA were detected. Moreover, levels of inflammatory cytokines including IL-6, IL-10, MCP-1, TNF-α were measured in the sera of mice. RESULTS: We found that the extract of MXF at dosages of 2.3-4.7g/kg could effectively diminish mortality rate, ameliorate lung edema and inflammation. Administration of MXF decoction significantly depressed the expression of IL-6, MCP-1 and TNF-α, and markedly increased expression of IL-10 in serum. Simultaneously, the extract was also found to reduce MDA and increase SOD in the lung tissue of mice. CONCLUSION: These data support the notion that the extract of MXF could treat Kidney-Yang deficiency syndrome in mice simultaneously infected with influenza A virus by reducing inflammation and increasing antioxidant activities.