RESUMEN

Acute idiopathic pancreatitis (AIP) has been rarely linked to SARS-CoV-2 and its mechanism is not completely understood. As a result, its management, due to the heterogeneity of the literature, may pose a challenge. This case report describes a 59-year-old female who presented to the emergency department with severe epigastric pain, fever, and a positive SARS-CoV-2 polymerase chain reaction (PCR) test. Imaging confirmed acute interstitial pancreatitis, which was successfully managed using the viral RNA polymerase inhibitor, remdesivir. Pancreatitis-associated complications, such as sepsis and shock, are recognized as significant factors contributing to extended hospitalization and increased mortality rates. The management of autoimmune pancreatitis poses a challenge due to the diverse existing literature, resulting in a lack of standardized approaches. Although the impact on inpatient mortality of remdesivir remains uncertain, early administration of RNA polymerase inhibitors could alleviate complications and positively impact the duration of hospitalization. Further research is important to create optimal management strategies for complications related to COVID-19-related pancreatitis.

RESUMEN

Introduction: Machine learning methods, coupled with a tremendous increase in computer power in recent years, are promising tools in modern drug design and drug repurposing. Methods: Machine learning predictive models, publicly available at chemosophia.com, were used to predict the bioactivity of recently synthesized platinum(IV) complexes against different kinds of diseases and medical conditions. Two novel QSAR models based on the BiS algorithm are developed and validated, capable to predict activities against the SARS-CoV virus and its RNA dependent RNA polymerase. Results: The internal predictive power of the QSAR models was tested by 10-fold cross-validation, giving cross-R2 from 0.863 to 0.903. 38 different activities, ranging from antioxidant, antibacterial, and antiviral activities, to potential anti-inflammatory, anti-arrhythmic and anti-malarial activity were predicted for a series of eighteen platinum(IV) complexes. Conclusion: Complexes 1, 3 and 13 have high generalized optimality criteria and are predicted as potential SARS-CoV RNA dependent RNA polymerase inhibitors.

RESUMEN

The emergence and spread of antiviral-resistant influenza viruses are of great concern. To minimize the public health risk, it is important to monitor antiviral susceptibilities of influenza viruses. Analyses of the antiviral susceptibilities of influenza A and B viruses have been conducted globally; however, those of influenza C and D viruses are limited. Here, we determined the susceptibilities of influenza C viruses representing all six lineages (C/Taylor, C/Yamagata, C/Sao Paulo, C/Aichi, C/Kanagawa, and C/Mississippi) and influenza D viruses representing four lineages (D/OK, D/660, D/Yama2016, and D/Yama2019) to RNA polymerase inhibitors (baloxavir and favipiravir) by using a focus reduction assay. All viruses tested were susceptible to both drugs. We then performed a genetic analysis to check for amino acid substitutions associated with baloxavir and favipiravir resistance and found that none of the viruses tested possessed these substitutions. Use of the focus reduction assay with the genotypic assay has proven valuable for monitoring the antiviral susceptibilities of influenza C and D viruses as well as influenza A and B viruses. Antiviral susceptibility monitoring of all influenza virus types should continue in order to assess the public health risks posed by these viruses.

Asunto(s)

Gripe Humana , Orthomyxoviridae , Humanos , Gripe Humana/tratamiento farmacológico , Antivirales/farmacología , Antivirales/uso terapéutico , Brasil , Farmacorresistencia Viral/genética

RESUMEN

Mycobacterium tuberculosis (Mtb) is considered to be a devastating pathogen worldwide, affecting millions of people globally. Several drugs targeting distinct pathways are utilized for the treatment of tuberculosis. Despite the monumental efforts being directed at the discovery of drugs for Mtb, the pathogen has also developed mechanisms to evade the drug action and host processes. Rifampicin was an early anti-tuberculosis drug, and is still being used as the first line of treatment. This study was carried out in order to characterize the in-depth rifampicin-mediated metabolic changes in Mtb, facilitating a better understanding of the physiological processes based on the metabolic pathways and predicted protein interactors associated with the dysregulated metabolome. Although there are various metabolomic studies that have been carried out on rifampicin mutants, this is the first study that reports a large number of significantly altered metabolites in wild type Mtb upon rifampicin treatment. In this study, a total of 173 metabolites, associated with pyrimidine, purine, arginine, phenylalanine, tyrosine, and tryptophan metabolic pathways, were significantly altered by rifampicin. The predicted host protein interactors of the rifampicin-dysregulated Mtb metabolome were implicated in transcription, inflammation, apoptosis, proteolysis, and DNA replication. Further, tricarboxylic acidcycle metabolites, arginine, and phosphoenolpyruvate were validated by multiple-reaction monitoring. This study provides a comprehensive list of altered metabolites that serves as a basis for understanding the rifampicin-mediated metabolic changes, and associated functional processes, in Mtb, which holds therapeutic potential for the treatment of Mtb.

RESUMEN

The circulation of avian influenza A viruses in poultry is a public health concern due to the potential transmissibility and severity of these viral infections. Monitoring the susceptibility of these viruses to antivirals is important for developing measures to strengthen the level of preparedness against influenza pandemics. However, drug susceptibility information on these viruses is limited. Here, we determined the susceptibilities of avian influenza A(H5N1), A(H5N2), A(H5N8), A(H7N7), A(H7N9), A(H9N1), and A(H9N2) viruses isolated in Japan to the antivirals approved for use there: an M2 inhibitor (amantadine), neuraminidase inhibitors (oseltamivir, peramivir, zanamivir, and laninamivir) and RNA polymerase inhibitors (baloxavir and favipiravir). Genotypic methods that detect amino acid substitutions associated with antiviral resistance and phenotypic methods that assess phenotypic viral susceptibility to drugs have revealed that these avian influenza A viruses are susceptible to neuraminidase and RNA polymerase inhibitors. These results suggest that neuraminidase and RNA polymerase inhibitors currently approved in Japan could be a treatment option against influenza A virus infections in humans.

Asunto(s)

Farmacorresistencia Viral , Gripe Aviar , Gripe Humana , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , ARN Polimerasas Dirigidas por ADN , Farmacorresistencia Viral/genética , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Humanos , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H5N2 del Virus de la Influenza A/efectos de los fármacos , Subtipo H7N7 del Virus de la Influenza A/efectos de los fármacos , Subtipo H7N9 del Virus de la Influenza A/efectos de los fármacos , Subtipo H9N2 del Virus de la Influenza A/efectos de los fármacos , Gripe Aviar/epidemiología , Gripe Aviar/virología , Gripe Humana/epidemiología , Gripe Humana/virología , Japón/epidemiología , Neuraminidasa/genética , Neuraminidasa/metabolismo , Oseltamivir/farmacología , Oseltamivir/uso terapéutico , Aves de Corral

RESUMEN

Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly resulted in a global pandemic with approximately 4 million deaths. Effective oral antiviral agents are urgently needed to treat coronavirus disease-2019 (COVID-19), block SARS-CoV-2 transmission, and prevent progression to severe illness. Molnupiravir (formerly EIDD-2801), a prodrug of beta-d-N4-hydroxycytidine (EIDD-1931) and an inhibitor of RNA-dependent RNA polymerase, possesses significant activity against SARS-CoV-2. Its prophylactic efficacy has been evidenced in a ferret model. Two phase-I trials (NCT04392219 and NCT04746183) have demonstrated that oral molnupiravir is safe and well-tolerated at therapeutic doses. After five-days of oral molnupiravir therapy, satisfactory efficacies, assessed by eliminating nasopharyngeal virus in patients with early and mild COVID-19, were disclosed in two phase-II trials (NCT04405739 and NCT04405570). Two phase-II/III trials, NCT04575597 and NCT04575584, with estimated enrollments of 1850 and 304 cases, respectively, are ongoing. The NCT04575597 recently released that molnupiravir significantly reduced the risk of hospitalization or death in adults experiencing mild or moderate COVID-19. To benefit individual and public health, clinical applications of molnupiravir to promptly treat COVID-19 patients and prevent SARS-CoV-2 transmission may be expected.

RESUMEN

Chronic wounds infected with pathogens such as Staphylococcus aureus represent a worldwide health concern, especially in patients with a compromised immune system. As antimicrobial resistance has become an immense global problem, novel antibiotics are urgently needed. One strategy to overcome this threatening situation is the search for drugs targeting novel binding sites on essential and validated enzymes such as the bacterial RNA polymerase (RNAP). In this work, we describe the establishment of an in vivo wound infection model based on the pathogen S. aureus and hairless Crl:SKH1-Hrhr (SKH1) mice. The model proved to be a valuable preclinical tool to study selected RNAP inhibitors after topical application. While rifampicin showed a reduction in the loss of body weight induced by the bacteria, an acceleration of wound healing kinetics, and a reduced number of colony forming units in the wound, the ureidothiophene-2-carboxylic acid 1 was inactive under in vivo conditions, probably due to strong plasma protein binding. The cocrystal structure of compound 1 with RNAP, that we hereby also present, will be of great value for applying appropriate structural modifications to further optimize the compound, especially in terms of plasma protein binding.

Asunto(s)

Infecciones Estafilocócicas , Infección de Heridas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , ARN Polimerasas Dirigidas por ADN , Humanos , Ratones , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus , Infección de Heridas/tratamiento farmacológico

RESUMEN

The filamentous actinomycete that produces the antibiotic GE23077 was isolated by the Lepetit Research Group from a soil sample collected in Thailand, and it was classified as a member of the genus Actinomadura on the basis of its morphology and cell-wall composition. Phylogenetic analysis based on 16S rRNA gene sequences indicated that this strain formed a distinct monophyletic line within the genus Actinomadura, and it was most closely related to Actinomadura bangladeshensis DSM 45347T (99.31 % similarity) and Actinomadura mexicana DSM 44485T (98.94 %). The GE23077-producing strain formed an extensively branched, non-fragmented vegetative mycelium; no pseudosporangia were formed and the arthrospores were organized in slightly twisted chains. The cell wall contained meso-2,6-diaminopimelic acid and the diagnostic sugar was madurose. The predominant menaquinone was MK-9(H6), with minor amounts of MK-9(H8) and MK-9(H4). The diagnostic phospholipids were phosphatidylinositol and diphosphatidylglycerol. The major cellular fatty acids were C16 : 0 and tuberculostearic acid (10-methyloctadecanoic acid), followed by minor amounts of C18:1ω9c, C16:1ω7c and 10-methylheptadecanoic acid. The genomic DNA G+C content was 71.77 mol%. Significant differences in the morphological, chemotaxonomic and biochemical data, and the low DNA-DNA relatedness between the GE23077-producing strain and closely related type strains clearly demonstrate that it represents a novel species of the genus Actinomadura, for which the name Actinomadura lepetitiana sp. nov. is proposed. The type strain is NRRL B-65521T(=LMG 31258T=DSM 109019T).

Asunto(s)

Actinobacteria/clasificación , Filogenia , Microbiología del Suelo , Actinobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tailandia , Vitamina K 2/análogos & derivados , Vitamina K 2/química

RESUMEN

Influenza A virus infections cause significant morbidity and mortality, and novel antivirals are urgently needed. Influenza RNA-dependent RNA polymerase (RdRp) activity has been acknowledged as a promising target for novel antivirals. In this study, a phenotypic versus target-based screening strategy was established to identify the influenza A virus inhibitors targeting the virus RNA transcription/replication steps by sequentially using an RdRp-targeted screen and a replication-competent reporter virus-based approach using the same compounds. To demonstrate the utility of this approach, a pilot screen of a library of 891 compounds derived from natural products was carried out. Quality control analysis indicates that the primary screen was robust for identification of influenza A virus inhibitors targeting RdRp activity. Finally, two hit candidates were identified, and one was validated as a putative RdRp inhibitor. This strategy can greatly reduce the number of false positives and improve the accuracy and efficacy of primary screening, thereby providing a powerful tool for antiviral discovery.

Asunto(s)

Antivirales/farmacología , Virus de la Influenza A/efectos de los fármacos , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Línea Celular , Evaluación Preclínica de Medicamentos , Humanos , Virus de la Influenza A/enzimología , Virus de la Influenza A/genética , Gripe Humana/virología , Proyectos Piloto , ARN Viral/genética , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismo , Replicación Viral/efectos de los fármacos

RESUMEN

Ascending Chlamydia trachomatis infection causes functional damage to the fallopian tubes, which may lead to ectopic pregnancy and infertility in women. Treatment failures using the standard regimens of doxycycline and azithromycin have been observed. We tested the polyketide-derived α-pyrone antibiotic Corallopyronin A (CorA) that inhibits the bacterial DNA dependent RNA polymerase and has strong activity against various extracellular and some intracellular bacteria. Extensive testing in cell culture infection models and in an ex vivo human fallopian tube model under different oxygen concentrations was performed to assess the anti-chlamydial efficacy of CorA at physiological conditions. CorA showed high efficacy against C. trachomatis (MICN/H: 0.5 µg/mL for serovar D and L2), C. muridarum (MICN/H: 0.5 µg/mL), and C. pneumoniae (MICN/H: 1 µg/mL) under normoxic (N) and hypoxic (H) conditions. Recoverable inclusion forming units were significantly lower already at 0.25 µg/mL for all tested chlamydiae. CorA at a concentration of 1 µg/mL was also effective against already established C. trachomatis and C. pneumoniae infections (up to 24 h.p.i.) in epithelial cells, while efficacy against C. muridarum was limited to earlier time points. A preliminary study using a C. muridarum genital infection model revealed corresponding limitations in the efficacy. Importantly, in an ex vivo human fallopian tube model, the growth of C. trachomatis was significantly inhibited by CorA at concentrations of 1-2 µg/mL under normoxic and hypoxic conditions. The overall high efficacies of CorA against C. trachomatis in cell culture and an ex vivo human fallopian tube model under physiological oxygen concentrations qualifies this drug as a candidate that should be further investigated.

RESUMEN

Fidaxomicin is an antibacterial drug in clinical use for treatment of Clostridium difficile diarrhea. The active ingredient of fidaxomicin, lipiarmycin A3 (Lpm), functions by inhibiting bacterial RNA polymerase (RNAP). Here we report a cryo-EM structure of Mycobacterium tuberculosis RNAP holoenzyme in complex with Lpm at 3.5-Å resolution. The structure shows that Lpm binds at the base of the RNAP "clamp." The structure exhibits an open conformation of the RNAP clamp, suggesting that Lpm traps an open-clamp state. Single-molecule fluorescence resonance energy transfer experiments confirm that Lpm traps an open-clamp state and define effects of Lpm on clamp dynamics. We suggest that Lpm inhibits transcription by trapping an open-clamp state, preventing simultaneous interaction with promoter -10 and -35 elements. The results account for the absence of cross-resistance between Lpm and other RNAP inhibitors, account for structure-activity relationships of Lpm derivatives, and enable structure-based design of improved Lpm derivatives.

Asunto(s)

Antibacterianos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Escherichia coli/efectos de los fármacos , Fidaxomicina/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/ultraestructura , Sitios de Unión , Microscopía por Crioelectrón , ARN Polimerasas Dirigidas por ADN/metabolismo , ARN Polimerasas Dirigidas por ADN/ultraestructura , Diseño de Fármacos , Farmacorresistencia Bacteriana/genética , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/ultraestructura , Fidaxomicina/química , Fidaxomicina/metabolismo , Transferencia Resonante de Energía de Fluorescencia , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Modelos Moleculares , Mutación , Mycobacterium tuberculosis/enzimología , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/ultraestructura , Unión Proteica , Conformación Proteica , Imagen Individual de Molécula , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/enzimología , Staphylococcus aureus/genética , Relación Estructura-Actividad

RESUMEN

6-O-(2-Nitrobenzyl)guanosine and 4-O-(2-nitrobenzyl)uridine triphosphates (NBGTP, NBUTP) were synthesized, and their biochemical and photophysical properties were evaluated. We synthesized NBUTP using the canonical triphosphate synthesis method and NBGTP from 2',3'-O-TBDMS guanosine via a triphosphate synthesis method by utilizing mild acidic desilylation conditions. Deprotection of the nitrobenzyl group in NBGTP and NBUTP proceeded within 60s by UV irradiation at 365nm. Experiments using NBGTP or NBUTP in T7-RNA transcription reactions showed that NBGTP could be useful for the photocontrol of transcription by UV irradiation.

Asunto(s)

ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Guanosina/farmacología , Transcripción Genética/efectos de los fármacos , Rayos Ultravioleta , Uridina Trifosfato/farmacología , Proteínas Virales/antagonistas & inhibidores , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Guanosina/análogos & derivados , Guanosina/síntesis química , Estructura Molecular , Relación Estructura-Actividad , Transcripción Genética/genética , Uridina Trifosfato/síntesis química , Uridina Trifosfato/química , Proteínas Virales/genética , Proteínas Virales/metabolismo

RESUMEN

Drug-resistant bacterial pathogens pose an urgent public-health crisis. Here, we report the discovery, from microbial-extract screening, of a nucleoside-analog inhibitor that inhibits bacterial RNA polymerase (RNAP) and exhibits antibacterial activity against drug-resistant bacterial pathogens: pseudouridimycin (PUM). PUM is a natural product comprising a formamidinylated, N-hydroxylated Gly-Gln dipeptide conjugated to 6'-amino-pseudouridine. PUM potently and selectively inhibits bacterial RNAP in vitro, inhibits bacterial growth in culture, and clears infection in a mouse model of Streptococcus pyogenes peritonitis. PUM inhibits RNAP through a binding site on RNAP (the NTP addition site) and mechanism (competition with UTP for occupancy of the NTP addition site) that differ from those of the RNAP inhibitor and current antibacterial drug rifampin (Rif). PUM exhibits additive antibacterial activity when co-administered with Rif, exhibits no cross-resistance with Rif, and exhibits a spontaneous resistance rate an order-of-magnitude lower than that of Rif. PUM is a highly promising lead for antibacterial therapy.

Asunto(s)

Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , ARN Polimerasas Dirigidas por ADN/antagonistas & inhibidores , Streptomyces/química , Animales , Antibacterianos/química , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , ARN Polimerasas Dirigidas por ADN/química , Farmacorresistencia Bacteriana , Femenino , Células HeLa , Humanos , Ratones , Ratones Endogámicos ICR , Microbiología del Suelo , Infecciones Estreptocócicas/tratamiento farmacológico , Streptococcus pyogenes/efectos de los fármacos , Transcripción Genética/efectos de los fármacos

RESUMEN

As we approach the global eradication of circulating wild-type polioviruses (PV), vaccination with oral poliovirus vaccine (OPV) has led to the emergence of circulating vaccine-derived poliovirus (cVDPV) and vaccine-associated paralytic poliomyelitis (VAPP). Complete cessation of all poliovirus infections may require stopping use of OPV and formulating improved vaccines and new antiviral drugs. Currently, no licensed drugs are available to treat chronically infected poliovirus excretors. Here, we created a modified PV expressing Gaussia Luciferase (Sb-Gluc) and developed a cell-based high-throughput screening (HTS) antiviral assay. Using the validated HTS assay, we screened the FDA-approved drug library of compounds and identified candidate agents capable of inhibiting PV replication. We then characterized antipoliovirus activity for the best hit, gemcitabine, a nucleoside analogue used in tumor chemotherapy. We found that gemcitabine inhibited PV Mahoney replication with an IC50 of 0.3 µM. It completely protected HeLa cells from PV-induced cytopathic effects at 25 µM, without detectable toxicity for cell viability. Furthermore, a gemcitabine metabolite directly inhibited the ability of PV RNA polymerase to synthesize or elongate PV RNA. Because PV RNA polymerase is somehow conserved among species in the Picornaviridae family, gemcitabine may be further developed as an attractive broad-spectrum antiviral for PV and others.

Asunto(s)

Antivirales/farmacología , Desoxicitidina/análogos & derivados , Poliovirus/efectos de los fármacos , Desoxicitidina/farmacología , Células HeLa , Ensayos Analíticos de Alto Rendimiento , Humanos , Ensayo de Placa Viral , Replicación Viral , Gemcitabina

RESUMEN

As a DNA damage sensor,poly (ADP-ribose) polymerase (PARP) is involved in a wide variety of cellular activities,such as DNA damage repair.PARP inhibitors regulate a series of cellular activities by inhibiting PARP function,which have become a focus of current research.Recently,several in vivo and in vitro studies showed that PARP inhibitors combined with radiotherapy effectively enhanced the efficacy of radiotherapy.This paper reviews the research advances in the mechanisms of action of PARP inhibitors and their combination with radiotherapy.

RESUMEN

The current standard of care for hepatitis C therapy is the combination of direct-acting antiviral (DAA) agents. These orally administered medications target the viral proteins and halt the hepatitis C virus lifecycle. Despite high cure rates with these novel drugs, virologic failure with DAAs are of mounting concern as real-world sustained virologic response 12 rates seem lower than expected. The mechanisms of virologic failure to DAAs are likely multifactorial, including baseline resistance variants, the efficacy of the agents used, and host factors. Salvage therapy for DAA virologic failures is an area of emerging research.

Asunto(s)

Antivirales/uso terapéutico , Farmacorresistencia Viral , Hepatitis C/tratamiento farmacológico , Inhibidores de la Síntesis del Ácido Nucleico/uso terapéutico , Inhibidores de Proteasas/uso terapéutico , Proteínas no Estructurales Virales/antagonistas & inhibidores , Antivirales/farmacología , Quimioterapia Combinada , Genotipo , Hepacivirus/genética , Hepacivirus/fisiología , Hepatitis C/genética , Hepatitis C/inmunología , Humanos , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Inhibidores de Proteasas/farmacología , ARN Viral/biosíntesis , Recurrencia , Retratamiento , Sofosbuvir/uso terapéutico , Insuficiencia del Tratamiento

RESUMEN

The treatment environment for chronic hepatitis C has undergone a revolution, particularly in genotype 1. Gone are interferon-based therapy and its associated tolerability challenges, inadequate response rates and numerous baseline factors that affect response to therapy. New and emerging treatment regimens employ all-oral combinations of direct-acting antiviral agents, and results of clinical trials suggest that these regimens routinely achieve cure rates >90%, even in patients who failed prior interferon-based triple therapy. In 2015, three all-oral FDA-approved regiments will be available for genotype 1 (sofosbuvir /ledipasvir, sofosbuvir/simeprevir, and paritaprevir/r/ombitasvir/dasabuvir). Furthermore, new treatment combinations appear to be more tolerable and require shorter duration of therapy. We provide an overview of the classes of direct-acting antiviral agents (DAAs), the clinical factors affecting their integration into combination therapies and recent findings from trials of such combination therapies in patients with genotype 1 HCV infection.

Asunto(s)

Antivirales/administración & dosificación , Inhibidores Enzimáticos/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Administración Oral , Ensayos Clínicos como Asunto , Quimioterapia Combinada/métodos , Humanos , Proteínas no Estructurales Virales/antagonistas & inhibidores

RESUMEN

Targeting PqsD is a promising novel approach to disrupt bacterial cell-to-cell-communication in Pseudomonas aeruginosa. In search of selective PqsD inhibitors, two series of benzamidobenzoic acids - one published as RNAP inhibitors and the other as PqsD inhibitors - were investigated for inhibitory activity toward the respective other enzyme. Additionally, novel derivatives were synthesized and biologically evaluated. By this means, the structural features needed for benzamidobenzoic acids to be potent and, most notably, selective PqsD inhibitors were identified. The most interesting compound of this study was the 3-Cl substituted compound 5 which strongly inhibits PqsD (IC50 6.2 µM) while exhibiting no inhibition of RNAP.

Asunto(s)

Antibacterianos/uso terapéutico , Benzoatos/uso terapéutico , Infecciones por Pseudomonas/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación

RESUMEN

In order to identify the inhibitors of hepatitis C virus (HCV) replication with a novel scaffold via a mechanistically unbiased approach, we screened our in-house library composed of ∼6000 compounds with various chemical structures by using the renilla luciferase-linked genotype 2a reporter virus, and we identified a series of compounds containing an indole moiety that were active against HCV replication. Based on this result, we further synthesized three groups of indole derivatives and evaluated their inhibitory effects on HCV replication. In the present structure-activity relationship study of these indole derivatives, we discovered that compound 12e was the most potent inhibitor of HCV replication with minimal cytotoxicity (EC50 = 1.1 µM, EC90 = 2.1 µM, and CC50 = 61.8 µM). We also confirmed that compound 12e caused a dose- and time-dependent reduction of viral RNA as well as viral protein levels in both genotype 2a J6/JFH1 RNA-transfected cells and genotype 1b Bart79I subgenomic replicon cells. Finally, a genetic mapping study of mutant viruses resistant to compound 12e revealed that NS5B RNA polymerase was the potential target. This finding was further validated by demonstration of inhibition of NS5B RNA polymerase in vitro by compound 12e (IC50 = 292 nM). Compound 12e may serve as a valuable candidate for the development of a new class of HCV NS5B RNA polymerase inhibitors in the future.

Asunto(s)

Antivirales/química , Antivirales/farmacología , Descubrimiento de Drogas/métodos , Hepacivirus/efectos de los fármacos , Indoles/química , Indoles/farmacología , Replicación Viral/efectos de los fármacos , Línea Celular , Genoma Viral , Hepacivirus/genética , Hepacivirus/fisiología , Hepatitis C/tratamiento farmacológico , Hepatitis C/virología , Humanos , ARN Viral/genética , ARN Viral/metabolismo , ARN Polimerasa Dependiente del ARN/metabolismo , Relación Estructura-Actividad , Proteínas no Estructurales Virales/metabolismo

RESUMEN

The bacterial RNA polymerase (RNAP) is an ideal target for the development of antimicrobial agents against drug-resistant bacteria. Especially, the switch region within RNAP has been considered as an attractive binding site for drug discovery. Here, we designed and synthesized a series of novel hybrid-type inhibitors of bacterial RNAP. The antimicrobial activities were evaluated using a paper disk diffusion assay, and selected derivatives were tested to determine their MIC values. The hybrid-type antimicrobial agent 29 showed inhibitory activity against Escherichia coli RNAP. The molecular docking study suggested that the RNAP switch region would be the binding site of 29.