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1.
Acta Virol ; 63(3): 261-269, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507191

RESUMO

Bovine viral diarrhea virus (BVDV) exists in two main biotypes: cytopathic (cp) and noncytopathic (ncp). Although some studies were done on the effect of interferon alpha (IFN-α) on BVDV, the effect of exogenous IFN against BVDV biotypes remains unclear. In the present study, we evaluated the comparative effect of exogenous human IFN-α (HuIFN-α) on different BVDV biotypes and genotypes. The results showed that exogenous HuIFN-α greatly inhibited the growth of different BVDV biotypes and genotypes. However, HuINF-α has a significant inhibitory effect on cp biotype compared to ncp one without significant variation between different genotypes. The effect of HuIFN-α on BVDV reached the maximum level at early stages of infection (0-20 h post infection) and increased in a dose-dependent manner (10-500 U/ml). Quantitative real-time RT-PCR was used to evaluate the effect of exogenous HuIFN-α on RNA synthesis of both BVDV biotypes. HuIFN-α reduced RNA production of cp by 4 logs compared to only 2 logs for ncp strains. Additionally, the antiviral effect of IFN-α against both BVDV biotypes seems to be independent of the RNA-dependent protein kinase (PKR) activation as assayed by direct analysis of in vivo phosphorylation of eIF2-α and by 2-aminopurine (2-AP) treatment. Collectively, these results indicated that the exogenous HuIFN-α treatment has an inhibitory effect not only on cp BVDV biotype but also on the ncp BVDV. The antiviral effect of exogenous HuIFN-α was biotype, time, dose but not genotype dependent. PKR has no role in the inhibitory effect suggesting that other IFN-antiviral pathways were involved. Keywords: BVDV biotypes; HuIFN-α; RNA synthesis; PKR-independent.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Vírus da Diarreia Viral Bovina , Interferon-alfa , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/tratamento farmacológico , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Replicação Viral/efeitos dos fármacos
2.
Acta Virol ; 63(3): 278-285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507193

RESUMO

Dengue virus (DENV) infection is one of the most widely-spread flavivirus infections with no effective antiviral drugs available. Peptide inhibitors have been considered as one of the best drug candidates due to their high specificity, selectivity in their interactions and minimum side effects. In this study, we employed computational studies using YASARA, HADDOCK server and PyMOL software to generate short and linear peptides based on a reference peptide, CP5-46A, to block DENV NS2B-NS3 protease. The inhibition potencies of the peptides were evaluated using in-house DENV2 serine protease and fluorogenic peptide substrates. In vitro analyses were performed to determine the peptides cytotoxicity and the inhibitory effects against DENV2 replication in WRL-68 cells. Our computational analyses revealed that the docking energy of AYA3, a 16 amino acid (aa) (-81.2 ± 10.6 kcal/mol) and AYA9, a 15 aa peptide (-83.8 ± 6.8 kcal/mol) to DENV NS2B-NS3 protease were much lower than the reference peptide (46 aa; -70.9 ± 7.8 kcal/mol) and the standard protease inhibitor, aprotinin (58 aa; -48.2 ± 10.6 kcal/mol). Both peptides showed significant inhibition against DENV2 NS2B-NS3 protease activity with IC50 values of 24 µM and 23 µM, respectively. AYA3 and AYA9 peptides also demonstrated approximately 68% and 83% of viral plaque reduction without significantly affecting cell viability at 50 µM concentration. In short, we generated short linear peptides with lower cytotoxic effect and substantial antiviral activities against DENV2. Further studies are required to investigate the inhibitory effects of these peptides in vivo. Keywords: peptide inhibitors; dengue virus; NS2B-NS3 protease; plaque reduction.


Assuntos
Antivirais , Vírus da Dengue , Peptídeos , Inibidores de Proteases , Replicação Viral , Antivirais/farmacologia , Biologia Computacional , Vírus da Dengue/enzimologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Peptídeos/síntese química , Peptídeos/farmacologia , Inibidores de Proteases/farmacologia , Replicação Viral/efeitos dos fármacos
3.
Acta Virol ; 63(3): 309-315, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507197

RESUMO

Influenza virus is activated by proteolytic cleavage of hemagglutinin by trypsin. After determining the optimal trypsin concentration, intracellular and extracellular influenza A/PR/8/34 (H1N1) and A/Victoria/361/2011 (H3N2) virus productions were compared in cultures treated with T-705 (favipiravir) and GS 4071 (an active form of oseltamivir). Although both drugs efficiently inhibited extracellular viral RNA release in a dose-dependent manner, T-705 inhibited it to the level of the inoculum without trypsin treatment, while GS 4071 inhibited it to a final level 10 times higher than that without trypsin. T-705 inhibited intracellular viral RNA production to the level of input virus in both trypsin-treated and untreated cells. In contrast, GS 4071 dose-dependently inhibited intracellular viral RNA production in cells treated with trypsin but allowed viral RNA synthesis. The level of maximum inhibition by GS 4071was 10 times higher than that of cells without trypsin and 1,000 times greater than the inoculum titer in cells without trypsin. T-705 inhibited both intracellular and extracellular virus production 1,000 and 10 times more strongly, respectively, than GS 4071. T-705 has powerful anti-influenza activity in the absence of trypsin and even in the trypsin-optimized growth condition, suggesting the therapeutic advantage in treatment of influenza complicated with bacterial pneumonia. Keywords: influenza; T-705; Tamiflu; trypsin; bacterial trypsin-like protease.


Assuntos
Amidas , Antivirais , Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Pirazinas , Tripsina , Amidas/farmacologia , Antivirais/farmacologia , Linhagem Celular , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Oseltamivir/farmacologia , Pirazinas/farmacologia , RNA Viral/biossíntese , Tripsina/farmacologia
4.
N Engl J Med ; 381(12): 1136-1147, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31532960

RESUMO

BACKGROUND: Maribavir is a benzimidazole riboside with activity against cytomegalovirus (CMV). The safety and efficacy of maribavir for preemptive treatment of CMV infection in transplant recipients is not known. METHODS: In a phase 2, open-label, maribavir dose-blinded trial, recipients of hematopoietic-cell or solid-organ transplants (≥18 years of age, with CMV reactivation [1000 to 100,000 DNA copies per milliliter]) were randomly assigned to receive maribavir at a dose of 400, 800, or 1200 mg twice daily or the standard dose of valganciclovir for no more than 12 weeks. The primary efficacy end point was the percentage of patients with a response to treatment, defined as confirmed undetectable CMV DNA in plasma, within 3 weeks and 6 weeks after the start of treatment. The primary safety end point was the incidence of adverse events that occurred or worsened during treatment. RESULTS: Of the 161 patients who underwent randomization, 159 received treatment, and 156 had postbaseline data available - 117 in the maribavir group and 39 in the valganciclovir group. The percentage of patients with postbaseline data available who had a response to treatment within 3 weeks was 62% among those who received maribavir and 56% among those who received valganciclovir. Within 6 weeks, 79% and 67% of patients, respectively, had a response (risk ratio, 1.20; 95% confidence interval, 0.95 to 1.51). The percentages of patients with a response to treatment were similar among the maribavir dose groups. Two patients who had a response to treatment had a recurrence of CMV infection within 6 weeks after starting maribavir at a dose of 800 mg twice daily; T409M resistance mutations in CMV UL97 protein kinase developed in both patients. The incidence of serious adverse events that occurred or worsened during treatment was higher in the maribavir group than in the valganciclovir group (52 of 119 patients [44%] vs. 13 of 40 [32%]). A greater percentage of patients in the maribavir group discontinued the trial medication because of an adverse event (27 of 119 [23%] vs. 5 of 40 [12%]). A higher incidence of gastrointestinal adverse events was reported with maribavir, and a higher incidence of neutropenia was reported with valganciclovir. CONCLUSIONS: Maribavir at a dose of at least 400 mg twice daily had efficacy similar to that of valganciclovir for clearing CMV viremia among recipients of hematopoietic-cell or solid-organ transplants. A higher incidence of gastrointestinal adverse events - notably dysgeusia - and a lower incidence of neutropenia were found in the maribavir group. (Funded by ViroPharma/Shire Development; EudraCT number, 2010-024247-32.).


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Infecções por Citomegalovirus/tratamento farmacológico , Citomegalovirus/fisiologia , Ribonucleosídeos/uso terapêutico , Valganciclovir/uso terapêutico , Viremia/tratamento farmacológico , Adulto , Idoso , Aloenxertos , Antivirais/efeitos adversos , Antivirais/farmacologia , Benzimidazóis/efeitos adversos , Benzimidazóis/farmacologia , Citomegalovirus/efeitos dos fármacos , Infecções por Citomegalovirus/virologia , Disgeusia/induzido quimicamente , Feminino , Gastroenteropatias/induzido quimicamente , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Transplante de Órgãos/efeitos adversos , Ribonucleosídeos/efeitos adversos , Ribonucleosídeos/farmacologia , Valganciclovir/efeitos adversos , Valganciclovir/farmacologia , Ativação Viral/efeitos dos fármacos
5.
Medicine (Baltimore) ; 98(32): e16683, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393369

RESUMO

Interferon-alpha (IFN-α) is currently the preferred antiviral treatment for children with chronic hepatitis B (CHB) aged >1-year-old. However, the evidence regarding the exact efficacy and safety in the real world is not sufficient. This study aimed to investigate the efficacy of IFN-α therapy in children with CHB and to provide a theoretical basis for practically identifying ideal antiviral therapies for CHB children.Clinical manifestations, baseline characteristics, related laboratory tests, and adverse events were retrospectively analyzed in children with CHB who visited the Children's Hospital of Fudan University, were treated with IFN-α and were followed up from January 2003 to October 2018.A total of 18 immune-active patients without advanced fibrosis were enrolled, and their average age at the start of treatment was 4.45 ±â€Š2.75 years old. IFN α-2b was administered subcutaneously by body surface area (BSA) category, based on 3 MU/m, for a median 48 weeks. Before treatment, the alanine aminotransferase (ALT) range was 81 to 409 U/L (median 158 U/L). The median hepatitis B virus (HBV)-DNA load was 9.89 × 10 IU/mL, and the HBV-DNA load varied from 3.10 × 10 to 4.56 × 10 IU/mL. The ALT levels of 17 children became normal at an average of 12 weeks during treatment, and those of 1 child became normal at 6 weeks after IFN-α withdrawal. Sixteen (88.9%, 16/18) children became HBV-DNA negative (<10 IU/mL) at an average of 24 weeks during treatment, while 1 became negative at 96 weeks after IFN-α withdrawal and 1 remained HBV-DNA positive. HBV e antigen (HBeAg) seroconversion occurred in 13 of 14 (92.9%, 13/14) HBeAg-positive patients at an average of 12 weeks during treatment. HBV s antigen (HBsAg) loss or seroconversion occurred in 4 (22.2%, 4/18) patients at an average of 21 weeks during treatment. Only mild flu-like symptoms and transient neutropenia appeared in some children at the early treatment stage. No severe abnormal results were observed in other laboratory parameters.The antiviral monotherapy of 48 weeks of IFN-α was well tolerated and good responded, which was associated with higher rates of HBeAg seroconversion and HBsAg clearance in the children in this study than in previously reported adults and pediatric patients.


Assuntos
Antivirais/administração & dosagem , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Adolescente , Antivirais/farmacologia , Criança , Pré-Escolar , China , Estudos de Coortes , Feminino , Seguimentos , Humanos , Injeções Subcutâneas , Interferon-alfa/farmacologia , Masculino , Soroconversão/efeitos dos fármacos , Carga Viral/efeitos dos fármacos
6.
J Agric Food Chem ; 67(33): 9241-9253, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31369258

RESUMO

Antiviral compounds targeting viral replicative processes have been studied as an alternative for the control of begomoviruses. Previously, we have reported that the peptide AmPep1 has strong affinity binding to the replication origin sequence of tomato yellow leaf curl virus (TYLCV). In this study, we describe the mechanism of action of this peptide as a novel alternative for control of plant-infecting DNA viruses. When AmPep1 was applied exogenously to tomato and Nicotiana benthamiana plants infected with TYLCV, a decrease in the synthesis of the two viral DNA strands (CS and VS) was observed, with a consequent delay in the development of disease progress in treated plants. The chemical mechanism of action of AmPep1 was deduced using Raman spectroscopy and molecular modeling showing the formation of chemical interactions such as H bonds and electrostatic interactions and the formation of π-π interactions between both biomolecules contributing to tampering with the viral replication.


Assuntos
Amaranthus/química , Antivirais/química , Antivirais/farmacologia , Begomovirus/efeitos dos fármacos , Peptídeos/química , Peptídeos/farmacologia , RNA Viral/química , Replicação Viral/efeitos dos fármacos , Begomovirus/química , Begomovirus/genética , Begomovirus/fisiologia , Sequências Repetidas Invertidas/efeitos dos fármacos , Lycopersicon esculentum/virologia , Doenças das Plantas/virologia , Proteínas de Plantas/química , RNA Viral/genética , Tabaco/virologia
7.
An Acad Bras Cienc ; 91(3): e20180621, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411258

RESUMO

Aristolochia triangularis Cham., is one of the most frequently used medicinal plant in Southern Brazil. Preparations containing the leaves and/or stems are traditionally used as anti-inflammatory, diuretic, as well as antidote against snakebites. This study screened A. triangularis extracts, fractions and isolated compounds for different bioactivities. A weak antiproliferative activity against human lung cancer cell line (A549) was observed only for chloroform fraction obtained from stems (CFstems - CC50: 2.93 µg/mL). Also, a moderate antimicrobial activity against Staphylococcus aureus was detected just for chloroform fraction obtained from leaves (CFleaves -13-16 mm inhibition zone). Additionally, two semi-purified fractions (CFstems-4 and CFleaves-4) selectively inhibited HSV-1 replication (IC50 values of 0.40 and 2.61 µg/mL, respectively), while only CFleaves showed promising results against Leishmania amazonensis. Fractionation of extracts resulted in the isolation of one neolignan (-) cubebin and one lignan (+) galbacin. However, these compounds are not responsible for the in vitro bioactivities herein detected. The presence of aristolochic acid I and aristolochic acid II in the crude ethanol extract of stems (CEEstems) and leaves (CEEleaves) was also investigated. The HPLC analysis of these extracts did not display any peak with retention time or UV spectra comparable to aristolochic acids I and II.


Assuntos
Aristolochia/química , Compostos Fitoquímicos/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antiprotozoários/farmacologia , Antivirais/farmacologia , Ácidos Aristolóquicos/química , Brasil , Fracionamento Químico , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia
8.
Chem Pharm Bull (Tokyo) ; 67(7): 654-665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257321

RESUMO

Quassinoids, one kind of triterpenoids with multiple bioactivities such as anti-cancer, anti-malarial, anti-oxidative, anti-microbial, anti-diabetic, anti-viral, and anti-inflammatory effects, have drawn much attention in recent years. Between 2004 and 2018, the structural characteristics and plant sources of 190 quassinoids were reported. Herein, the structure-activity relationships (SARs) of quassinoids along with the anti-cancer mechanisms of four representative quassinoids, eurycomanone, bruceine D, dehydrobruceine B, and brusatol are discussed. This review might be useful for further research and development of quassinoids.


Assuntos
Antineoplásicos Fitogênicos/química , Quassinas/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Plantas/química , Plantas/metabolismo , Plasmodium falciparum/efeitos dos fármacos , Quassinas/isolamento & purificação , Quassinas/farmacologia , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos
9.
Vet Microbiol ; 235: 21-24, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282375

RESUMO

Occurrence of avian influenza (AI) with Neuraminidase (NA) mutations which confer reduced neuraminidase inhibitor (NAI) susceptibility has remained a cause of concern. The susceptibility to NAIs of 67 highly pathogenic avian influenza H5N1 viruses isolated during 2006-2012 in India was tested in phenotypic fluorescence-based NA inhibition assay, sequence analysis and in ovo. One isolate showed a novel NA I117T amino acid substitution (N2 numbering) and eight isolates showed previously known NAI-resistance marker mutations (I117V, E119D, N294S, total 9/67). The overall incidence of resistant variants was 13.4%. The novel I117T substitution reduced oseltamivir susceptibility by 18.6-fold and zanamivir susceptibility by 11.8-fold, compared to the wild type AI H5N1virus, thus showed cross-resistance to both oseltamivir and zanamivir in NA inhibition assays. However, the other two isolates with I117V substitution were sensitive to both the NAIs. In addition, the comparison of growth of the I117T and I117V variants in presence of NAI's in the in ovo assays exhibited difference in growth levels. The present study reports the natural occurrence of a novel I117T mutation in AI H5N1 virus conferring cross-resistance to oseltamivir and zanamivir highlighting the urgent need of antiviral surveillance of AI viruses.


Assuntos
Antivirais/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Neuraminidase/genética , Oseltamivir/farmacologia , Proteínas Virais/genética , Zanamivir/farmacologia , Substituição de Aminoácidos , Animais , Galinhas , Farmacorresistência Viral , Índia , Virus da Influenza A Subtipo H5N1/genética , Concentração Inibidora 50 , Mutação de Sentido Incorreto , Zigoto
10.
J Microbiol Biotechnol ; 29(7): 1155-1164, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31280524

RESUMO

Lichens contain diverse bioactive secondary metabolites with various chemical and biological properties, which have been widely studied. However, details of the inhibitory mechanisms of their secondary metabolites against influenza A virus (IAV) have not been documented. Here, we investigated the antiviral effect of lichen extracts, obtained from South Korea, against IAV in MDCK cells. Of the lichens tested, Nipponoparmelia laevior (LC24) exhibited the most potent inhibitory effect against IAV infection. LC24 extract significantly increased cell viability, and reduced apoptosis in IAV-infected cells. The LC24 extract also markedly reduced (~ 3.2 logfold) IAV mRNA expression after 48 h of infection. To understand the antiviral mechanism of LC24 against IAV, proteomic (UPLC-HDMSE) analysis was performed to compare proteome modulation in IAV-infected (V) vs. mock (M) and LC24+IAV (LCV) vs. V cells. Based on Ingenuity Pathway Analysis (IPA), LC24 inhibited IAV infection by modulating several antiviral-related genes and proteins (HSPA4, HSPA5, HSPA8, ANXA1, ANXA2, HIF-1α, AKT1, MX1, HNRNPH1, HNRNPDL, PDIA3, and VCP) via different signaling pathways, including HIF-1α signaling, unfolded protein response, and interferon signaling. These molecules were identified as the specific biomarkers for controlling IAV in vitro and further confirmation of their potential against IAV in vivo is required. Our findings provide a platform for further studies on the application of lichen extracts against IAV.


Assuntos
Antivirais/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Líquens/química , Infecções por Orthomyxoviridae/metabolismo , Animais , Antivirais/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cães , Líquens/metabolismo , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/virologia , Proteômica , RNA Mensageiro/metabolismo , República da Coreia , Transdução de Sinais/efeitos dos fármacos , Proteínas Virais/genética
11.
J Agric Food Chem ; 67(31): 8468-8475, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31310114

RESUMO

Fermentation of the fungal strain Skeletocutis sp. originating from Mount Elgon Natural Reserve in Kenya, followed by bioassay guided fractionation led to the isolation of 12 previously undescribed metabolites named skeletocutins A-L (1-5 and 7-13) together with the known tyromycin A (6). Their structures were assigned by NMR spectroscopy complemented by HR-ESIMS. Compounds 1-6 and 11-13 exhibited selective activities against Gram-positive bacteria, while compound 10 weakly inhibited the formation of biofilm of Staphylococcus aureus. The isolated metabolites were also evaluated for inhibition of L-leucine aminopeptidase, since tyromycin A had previously been reported to possess such activities but only showed weak effects. Furthermore, all compounds were tested for antiviral activity against Hepatitis C virus (HCV), and compound 6 moderately inhibited HCV infectivity with an IC50 of 6.6 µM.


Assuntos
Antibacterianos/farmacologia , Polyporales/química , Madeira/microbiologia , Antibacterianos/química , Antibacterianos/metabolismo , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Quênia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Polyporales/crescimento & desenvolvimento , Polyporales/isolamento & purificação , Polyporales/metabolismo
12.
J Agric Food Chem ; 67(31): 8459-8467, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31339701

RESUMO

Novel purine nucleoside derivatives containing a sulfonamide moiety were prepared, as well as their antiviral activities against potato virus Y (PVY), cucumber mosaic virus (CMV), and tobacco mosaic virus (TMV) were evaluated. The antiviral mechanisms of the compounds were investigated. Results showed that most of the compounds had good antiviral activities. Compound 5 at 500 µg/mL exhibited excellent curative and protective activities of 52.5% and 60.0% and of 52.0% and 60.2% for PVY and CMV, respectively, which are higher than those of ningnanmycin (48.1%, 49.6%; 45.3%, 47.7%), ribavirin (38.3%, 48.2%; 40.8%, 45.5%), and chitosan oligosaccharide (32.5%, 33.8%; 35.1%, 34.6%). Moreover, compound 5 displayed good inactivating activity against TMV, with an EC50 value of 48.8 µg/mL, which is better than that of ningnanmycin (84.7 µg/mL), ribavirin (150.4 µg/mL), and chitosan oligosaccharide (521.3 µg/mL). The excellent antiviral activity of compound 5 is related to its immune induction effect which can regulate the physiological and biochemical processes in plants, including defense-related enzyme activities, defense-related genes, and photosynthesis-related proteins. These results indicate that purine nucleoside derivatives containing a sulfonamide moiety are worthy of further research and development as new antiviral agents.


Assuntos
Antivirais/química , Antivirais/farmacologia , Nucleosídeos de Purina/química , Nucleosídeos de Purina/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Antivirais/síntese química , Cucumovirus/efeitos dos fármacos , Desenho de Drogas , Estrutura Molecular , Potyvirus/efeitos dos fármacos , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos
13.
Virol J ; 16(1): 87, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266524

RESUMO

BACKGROUND: Human infection with avian influenza H7N9 virus was first reported in 2013. Since the fifth epidemic, a highly pathogenic avian influenza (HPAI) H7N9 virus has emerged and caused 33 human infections. Several potential NAI resistance sites have been found in human cases. However, the drug susceptibility and replication ability of HPAI H7N9 virus with such substitutions have not yet been studied. METHODS: Thirty-three HPAI H7N9 virus strains were isolated from human cases in China, and then sequences were analyzed to identify potential NAI resistance sites. Recombinant influenza viruses were generated to evaluate the effect of NA amino acid substitutions on NAI (oseltamivir or zanamivir) susceptibility and viral replication efficiency in MDCK cells. RESULTS: Four potential NAI resistance sites, R292 K, E119V, A246T or H274Y, were screened. All four substitutions conferred either reduced or highly reduced susceptibility to oseltamivir or zanamivir. 292 K not only highly reduced the susceptibility of HPAI H7N9 to oseltamivir but also induced an increase in the IC50 of zanamivir. 119 V or 274Y conferred reduced susceptibility of HPAI H7N9 to oseltamivir. Additionally, 246 T conferred reduced susceptibility to zanamivir. All tested NAI-resistant viruses were capable of replication in MDCK cells. The virus yields of rg006-NA292K were lower than those of rg006-NA292R at 24, 48, 72 and 96 h postinfection (P<0.05). Rg006-NA119V, rg006-NA246T or rg006-NA274Y showed comparable replication capacity to wild-type virus (except for rg006-NA274Y at 96 h, P<0.05). CONCLUSIONS: All 4 amino acid substitutions (R292 K, E119V, A246T or H274Y) in NA reduced the susceptibility of HPAI H7N9 to NAIs. The NAI-resistant mutations in HPAI H7N9, in most cases, did not reduce the replication ability of the virus in mammalian cells. Special attention needs to be paid to these mutations, and the development of new anti-H7N9 drugs is of great importance.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Subtipo H7N9 do Vírus da Influenza A/efeitos dos fármacos , Subtipo H7N9 do Vírus da Influenza A/genética , Influenza Humana/virologia , Replicação Viral/efeitos dos fármacos , Substituição de Aminoácidos , Animais , Galinhas , Cães , Farmacorresistência Viral/genética , Humanos , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Influenza Aviária , Células Madin Darby de Rim Canino , Neuraminidase/antagonistas & inibidores , Oseltamivir/farmacologia , Zanamivir/farmacologia
14.
Chem Biol Interact ; 308: 294-303, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158333

RESUMO

The emergence of multidrug resistant (MDR) pathogens is a global threat and has created problems in providing adequate treatment of many infectious diseases. Although the conventional antimicrobial agents are quite effective against several pathogens, yet there is a need for more effective antimicrobial agents against MDR pathogens. Herbal drugs and phytochemicals have been used for their effective antimicrobial activity from ancient times and there is an increasing trend for development of plant based natural products for the prevention and treatment of pathogenic diseases. One of the strategies for effective resistance modification is the use of antimicrobial agent-phytochemical combinations that will neutralize the resistance mechanism, enabling the drug to still be effective against resistant microbes. These phytochemicals can work by several strategies, such as inhibition of target modifying and drug degrading enzymes or as efflux pumps inhibitors. A plethora of herbal extracts, essential oils and isolated pure compounds have been reported to act synergistically with existing antibiotics, antifungals and chemotherapeutics and augment the activity of these drugs. Considerable increases in the susceptibility pattern of several microbes towards the natural antimicrobials and their combinations were observed as indicated by significant decline in minimum inhibitory concentrations. This review paper summarizes the current developments regarding synergistic interactions of plant extracts and isolated pure compounds in combination with existing antibacterial, antifungal agents and chemotherapeutics. The effect of these agents on the susceptibility patterns of these pathogens and possible mechanisms of action are described in detail. In conclusion, many phytochemicals in combination with existing drugs were found to act as resistance modifying agents and proper combinations may rescue the efficacy of important lifesaving antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Antifúngicos/química , Antifúngicos/farmacologia , Antivirais/química , Antivirais/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Vírus de DNA/efeitos dos fármacos , Sinergismo Farmacológico , Fungos/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , beta-Lactamases/química , beta-Lactamases/metabolismo
15.
MMWR Morb Mortal Wkly Rep ; 68(24): 544-551, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31220057

RESUMO

Influenza activity* in the United States during the 2018-19 season (September 30, 2018-May 18, 2019) was of moderate severity (1). Nationally, influenza-like illness (ILI)† activity began increasing in November, peaked during mid-February, and returned to below baseline in mid-April; the season lasted 21 weeks,§ making it the longest season in 10 years. Illness attributed to influenza A viruses predominated, with very little influenza B activity. Two waves of influenza A were notable during this extended season: influenza A(H1N1)pdm09 viruses from October 2018 to mid-February 2019 and influenza A(H3N2) viruses from February through May 2019. Compared with the 2017-18 influenza season, rates of hospitalization this season were lower for adults, but were similar for children. Although influenza activity is currently below surveillance baselines, testing for seasonal influenza viruses and monitoring for novel influenza A virus infections should continue year-round. Receiving a seasonal influenza vaccine each year remains the best way to protect against seasonal influenza and its potentially severe consequences.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Vigilância da População , Adolescente , Adulto , Idoso , Antivirais/farmacologia , Criança , Mortalidade da Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Farmacorresistência Viral , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza B/efeitos dos fármacos , Vírus da Influenza B/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/química , Influenza Humana/mortalidade , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Pneumonia/mortalidade , Estações do Ano , Índice de Gravidade de Doença , Estados Unidos/epidemiologia , Adulto Jovem
16.
Chemotherapy ; 64(1): 1-7, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31234166

RESUMO

Infections with herpes simplex virus type (HSV)-1 and HSV-2 are distributed worldwide. Although standard therapies with acyclovir and other synthetic drugs are available, the safety and efficacy of these drugs are limited due to the development of drug resistance and adverse side effects. The literature on essential oils and isolated compounds was reviewed regarding their antiviral activities against HSV-1 and HSV-2. The present overview aims to review experimental data and clinical trials focusing on the antiviral activity of selected essential oils and isolated oil components. HSV was found to be susceptible to many essential oils and their constituents. Whereas some essential oils and compounds exhibit direct virucidal activity or inhibit intracellular replication, many essential oils and compounds interact with HSV particles thereby inhibiting cell adsorption. Ayclovir-resistant HSV strains are also susceptible to essential oils since their mode of action is different from the synthetic drug. There are numerous publications on the antiherpetic activity of essential oils and their isolated active compounds. This field of research is still growing, and more clinical trials are required to explore the full potential of different essential oils for the topical treatment of herpetic infections.


Assuntos
Herpes Simples/tratamento farmacológico , Óleos Voláteis/uso terapêutico , Antivirais/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios Clínicos como Assunto , Humanos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Simplexvirus/efeitos dos fármacos , Simplexvirus/fisiologia
17.
Eur J Med Chem ; 178: 606-622, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31226653

RESUMO

The hydrophobic pocket within viral capsid protein 1 is a target to combat the rhino- and enteroviruses (RV and EV) using small molecules. The highly conserved amino acids lining this pocket enable the development of antivirals with broad-spectrum of activity against numerous RVs and EVs. Inhibitor binding blocks: the attachment of the virion to the host cell membrane, viral uncoating, and/or production of infectious virus particles. Syntheses and biological studies of the most well-known antipicornaviral capsid binders have been reviewed and we propose next steps in this research.


Assuntos
Antivirais/farmacologia , Capsídeo/metabolismo , Enterovirus/efeitos dos fármacos , Antivirais/química , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Enterovirus/química , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
18.
BMC Bioinformatics ; 20(1): 297, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159726

RESUMO

BACKGROUND: Host factors of influenza virus replication are often found in key topological positions within protein-protein interaction networks. This work explores how protein states can be manipulated through controllability analysis: the determination of the minimum manipulation needed to drive the cell system to any desired state. Here, we complete a two-part controllability analysis of two protein networks: a host network representing the healthy cell state and an influenza A virus-host network representing the infected cell state. In this context, controllability analyses aim to identify key regulating host factors of the infected cell's progression. This knowledge can be utilized in further biological analysis to understand disease dynamics and isolate proteins for study as drug target candidates. RESULTS: Both topological and controllability analyses provide evidence of wide-reaching network effects stemming from the addition of viral-host protein interactions. Virus interacting and driver host proteins are significant both topologically and in controllability, therefore playing important roles in cell behavior during infection. Functional analysis finds overlap of results with previous siRNA studies of host factors involved in influenza replication, NF-kB pathway and infection relevance, and roles as interferon regulating genes. 24 proteins are identified as holding regulatory roles specific to the infected cell by measures of topology, controllability, and functional role. These proteins are recommended for further study as potential antiviral drug targets. CONCLUSIONS: Seasonal outbreaks of influenza A virus are a major cause of illness and death around the world each year with a constant threat of pandemic infection. This research aims to increase the efficiency of antiviral drug target discovery using existing protein-protein interaction data and network analysis methods. These results are beneficial to future studies of influenza virus, both experimental and computational, and provide evidence that the combination of topology and controllability analyses may be valuable for future efforts in drug target discovery.


Assuntos
Antivirais/farmacologia , Sistemas de Liberação de Medicamentos , Descoberta de Drogas , Interações Hospedeiro-Patógeno , Mapas de Interação de Proteínas , Humanos , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/metabolismo , RNA Interferente Pequeno/metabolismo , Reprodutibilidade dos Testes , Replicação Viral/efeitos dos fármacos
19.
Life Sci ; 231: 116540, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176778

RESUMO

MRP4 is an ABC membrane transporter involved in clinical outcomes as it is located in many tissues that manages the transport and the elimination of many drugs. This review explores the implication of MRP4 in clinical pharmacology and the importance of its genetic variability. Although there is no specific recommendation regarding the study of MRP4 in drug development, it should be considered when drugs are eliminated by the kidney or liver or when drug-drug interactions are expected.


Assuntos
Antineoplásicos/farmacologia , Antivirais/farmacologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Animais , Antineoplásicos/farmacocinética , Antivirais/farmacocinética , Interações de Medicamentos , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Farmacogenética , Farmacocinética , Farmacologia
20.
Eur J Med Chem ; 178: 64-80, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31176096

RESUMO

Encouraged by our earlier discovery of neuraminidase inhibitors targeting 150-cavity or 430-cavity, herein, to yield more potent inhibitors, we designed, synthesized, and biologically evaluated a series of novel oseltamivir derivatives via modification of C-1 and C5-NH2 of oseltamivir by exploiting 150-cavity and/or 430-cavity. Among the synthesized compounds, compound 15e, the most potent N1-selective inhibitor targeting 150-cavity, showed 1.5 and 1.8 times greater activity than oseltamivir carboxylate (OSC) against N1 (H5N1) and N1 (H5N1-H274Y). In cellular assays, 15e also exhibited greater potency than OSC against H5N1 with EC50 of 0.66 µM. In addition, 15e demonstrated low cytotoxicity in vitro and low acute toxicity in mice. Molecular docking studies provided insights into the high potency of 15e against N1 and N1-H274Y mutant NA. Overall, we envisioned that the significant breakthrough in the discovery of potent group-1-specific neuraminidase inhibitors may lead to further investigation of more potent anti-influenza agents.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Neuraminidase/antagonistas & inibidores , Oseltamivir/análogos & derivados , Oseltamivir/farmacologia , Proteínas Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/química , Antivirais/toxicidade , Domínio Catalítico , Linhagem Celular , Galinhas , Desenho de Drogas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/toxicidade , Feminino , Influenzavirus A/enzimologia , Influenzavirus B/enzimologia , Masculino , Camundongos , Simulação de Acoplamento Molecular , Neuraminidase/química , Oseltamivir/síntese química , Oseltamivir/toxicidade , Proteínas Virais/química
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