Optimization of 4-Anilinoquinolines as Dengue Virus Inhibitors

Emerging viral infections, including those caused by dengue virus (DENV) and Venezuelan Equine Encephalitis virus (VEEV), pose a significant global health challenge. Here, we report the preparation and screening of a series of 4-anilinoquinoline libraries targeting DENV and VEEV. This effort generated a series of lead compounds, each occupying a distinct chemical space, including 3-((6-bromoquinolin-4-yl)amino)phenol (12), 6-bromo-N-(5-fluoro-1H-indazol-6-yl)quinolin-4-amine (50) and 6-((6-bromoquinolin-4-yl)amino)isoindolin-1-one (52), with EC50 values of 0.63–0.69 µM for DENV infection. These compound libraries demonstrated very limited toxicity with CC50 values greater than 10 µM in almost all cases. Additionally, the lead compounds were screened for activity against VEEV and demonstrated activity in the low single-digit micromolar range, with 50 and 52 demonstrating EC50s of 2.3 µM and 3.6 µM, respectively. The promising results presented here highlight the potential to further refine this series in order to develop a clinical compound against DENV, VEEV, and potentially other emerging viral threats.

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Transcriptional response of Wolbachia-transinfected Aedes aegypti mosquito cells to dengue virus at early stages of infection

Journal of General Virology ◽

10.1099/jgv.0.001694 ◽

2022 ◽

Vol 103 (1) ◽

Author(s):

Michael Leitner ◽

Kayvan Etebari ◽

Sassan Asgari

Keyword(s):

Aedes Aegypti ◽

Dengue Virus ◽

Viral Infections ◽

Transcriptional Response ◽

Denv Infection ◽

Content Type ◽

Public Health Burden ◽

Immune Genes ◽

Link Type ◽

Early Stages

Mosquito-borne flaviviruses are responsible for viral infections and represent a considerable public health burden. Aedes aegypti is the principal vector of dengue virus (DENV), therefore understanding the intrinsic virus–host interactions is vital, particularly in the presence of the endosymbiont Wolbachia, which blocks virus replication in mosquitoes. Here, we examined the transcriptional response of Wolbachia -transinfected Ae. aegypti Aag2 cells to DENV infection. We identified differentially expressed immune genes that play a key role in the activation of anti-viral defence such as the Toll and immune deficiency pathways. Further, genes encoding cytosine and N6-adenosine methyltransferases and SUMOylation, involved in post-transcriptional modifications, an antioxidant enzyme, and heat-shock response were up-regulated at the early stages of DENV infection and are reported here for the first time. Additionally, several long non-coding RNAs were among the differentially regulated genes. Our results provide insight into Wolbachia -transinfected Ae. aegypti’s initial virus recognition and transcriptional response to DENV infection.

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Dengue virus type 2 replication is limited by activation of NOD2 and its interactions with RIP2 and MAVS adaptors in THP-1 macrophage-like cells

10.22541/au.161883666.69158067/v1 ◽

2021 ◽

Author(s):

Diana Domínguez-Martínez ◽

Daniel Nuñez Avellaneda ◽

Juan Castillo Cruz ◽

Gloria León-Avila ◽

BLANCA GARCIA-PEREZ ◽

...

Keyword(s):

Dengue Virus ◽

Viral Infections ◽

Denv Infection ◽

Human Macrophage ◽

Infection Period ◽

Viral Loads ◽

Protein Levels ◽

Mock Control

The nucleotide-binding domain (NBD) and leucine-rich repeat receptors, such as NOD-like receptors (NLRs), have pivotal functions in the innate immune response to various viral infections participating during the recognition of pathogens and activation of signaling pathways. One NLR, NOD2, is a dynamic protein that is activated in the presence of viral genomes and metabolites. However, its participation in combating a dengue virus (DENV) infection remains unclear. The aim of this study was to determine the role of NOD2 in macrophage-like THP-1 cells during an in vitro infection with DENV type 2 (DENV2). The interactions of NOD2 with RIP2 and MAVS was examined in DENV2-infected and agonist-stimulated cells. The effects of downregulating NOD2 expression or signaling on virus loads was also evaluated. The cellular mRNA expression and protein levels of NOD2 on cells under the stimuli were quantified with RT-PCR, Western blot and indirect immunofluorescence. Both the mRNA and protein expression of NOD2 was enhanced in response to DENV-2 infection. Interactions of NOD2 with RIP2 and MAVS, analyzed with confocal microscopy and co-immunoprecipitation assays, were time-dependent and increased in the post-infection period, between 6 and 24 h. After silencing NOD2 expression, DENV2-infected cells displayed greater viral loads and decreased expression of IL-8 and IFN-α (measured in supernatants obtained from the cells), compared to the uninfected (mock control) cells or those transfected with irrelevant-siRNA. Thus, in response to a DENV2 infection, NOD2 was activated in THP-1 human macrophage-like cells, the production of IL-8 and IFN-α was enhanced, and viral replication was limited.

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The role of different serotypes and dengue virus concentration in the prognosis of dengue shock syndrome in children

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v10i3.1509 ◽

2019 ◽

Vol 10 (3) ◽

Author(s):

Tram Van Ta ◽

Hai Thanh Tran ◽

Quyen Nguyen Than Ha ◽

Xuong Tuyet Nguyen ◽

Vu Kien Tran ◽

...

Keyword(s):

Dengue Virus ◽

Dengue Infection ◽

Dengue Shock Syndrome ◽

Denv Infection ◽

Virus Concentration ◽

Denv Serotypes ◽

Significant Difference ◽

Almost All ◽

The Relationship

Dengue haemorrhagic fever (DHF) is a burden of disease in tropical countries, caused by any one of four-dengue virus (DENV) serotypes (DENV-1 to DENV-4). Although there have been many studies on patients with DHF, many things remain unclear, including the role of DENV serotypes and DENV concentration. The objective of this study was to determine the role of different serotypes and DENV concentration in the prognosis of dengue shock syndrome. This was a prospective cohort study, conducted to show information relating to patients’ conditions, such as hematocrit, platelet, leukocytes, and DENV concentration and the differences between DENV serotypes. The study also expressed the relationship between two groups, DHF without shock and DHF with shock, in terms of immune status, different DENV serotypes, and DENV concentration. Two-hundred and thirty-four patients were serologically confirmed as having a DENV infection. On hospital admission day (fever within 72 hours), results showed that almost all patients had a secondary dengue infection (76.5 %). DENV-1 accounted for the highest number of cases (61.11%), and DENV-4 accounted for the lowest (0.43%). No statistically significant difference was found when comparing the two groups (DHF with shock and DHF without shock) or when comparing the groups of different DENV serotypes. The study concluded that different DENV serotypes or DENV concentration in the first day of hospitalization (fever within 72 hours) cannot be used for prognostic of DSS.

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Berberine Inhibits Dengue Virus through Dual Mechanisms

Molecules ◽

10.3390/molecules26185501 ◽

2021 ◽

Vol 26 (18) ◽

pp. 5501

Author(s):

Thippayawan Ratanakomol ◽

Sittiruk Roytrakul ◽

Nitwara Wikan ◽

Duncan R. Smith

Keyword(s):

Dengue Virus ◽

Viral Infections ◽

Denv Infection ◽

Nonstructural Proteins ◽

Viral Production ◽

Dual Effect ◽

Traditional Medicines ◽

Cellular Effects ◽

Viral Egress ◽

Tropical Areas

Mosquito transmitted viruses, particularly those of the genus Flavivirus, are a significant healthcare burden worldwide, especially in tropical and sub-tropical areas. However, effective medicines for these viral infections remains lacking. Berberine (BBR) is an alkaloid found in some plants used in traditional medicines in Southeast Asia and elsewhere, and BBR has been shown to possess anti-viral activities. During a screen for potential application to mosquito transmitted viruses, BBR was shown to have virucidal activity against dengue virus (DENV; IC50 42.87 µM) as well as against Zika virus (IC50 11.42 µM) and chikungunya virus (IC50 14.21 µM). BBR was shown to have cellular effects that lead to an increase in cellular DENV E protein without a concomitant effect on DENV nonstructural proteins, suggesting an effect on viral particle formation or egress. While BBR was shown to have an effect of ERK1/2 activation this did not result in defects in viral egress mechanisms. The primary effect of BBR on viral production was likely to be through BBR acting through AMPK activation and disruption of lipid metabolism. Combined these results suggest that BBR has a dual effect on DENV infection, and BBR may have the potential for development as an anti-DENV antiviral.

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Recent Insights Into the Molecular Mechanism of Toll-Like Receptor Response to Dengue Virus Infection

Frontiers in Microbiology ◽

10.3389/fmicb.2021.744233 ◽

2021 ◽

Vol 12 ◽

Author(s):

Mohammad Enamul Hoque Kayesh ◽

Michinori Kohara ◽

Kyoko Tsukiyama-Kohara

Keyword(s):

Dengue Virus ◽

Viral Infections ◽

Denv Infection ◽

Viral Disease ◽

Innate Immune Responses ◽

Dengue Vaccine ◽

Medical Interventions ◽

Stage Development ◽

Tlr Signaling Pathway ◽

Made In

Dengue is the most prevalent and rapidly spreading mosquito-borne viral disease caused by dengue virus (DENV). Recently, DENV has been affecting humans within an expanding geographic range due to the warming of the earth. Innate immune responses play a significant role in antiviral defense, and Toll-like receptors (TLRs) are key regulators of innate immunity. Therefore, a detailed understanding of TLR and DENV interactions is important for devising therapeutic and preventive strategies. Several studies have indicated the ability of DENV to modulate the TLR signaling pathway and host immune response. Vaccination is considered one of the most successful medical interventions for preventing viral infections. However, only a partially protective dengue vaccine, the first licensed dengue vaccine CYD-TDV, is available in some dengue-endemic countries to protect against DENV infection. Therefore, the development of a fully protective, durable, and safe DENV vaccine is a priority for global health. Here, we demonstrate the progress made in our understanding of the host response to DENV infection, with a particular focus on TLR response and how DENV avoids the response toward establishing infection. We also discuss dengue vaccine candidates in late-stage development and the issues that must be overcome to enable their success.

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Oligonucleotide-Based Approaches to Inhibit Dengue Virus Replication

Molecules ◽

10.3390/molecules26040956 ◽

2021 ◽

Vol 26 (4) ◽

pp. 956

Author(s):

Kingshuk Panda ◽

Kalichamy Alagarasu ◽

Deepti Parashar

Keyword(s):

Dengue Virus ◽

Viral Replication ◽

Viral Infections ◽

Public Health Problem ◽

Denv Infection ◽

Viral Rna ◽

Effective Vaccine ◽

Cellular Processes ◽

Antiviral Therapies ◽

Life Threatening

Dengue fever is one of the most common viral infections affecting humans. It is an expanding public health problem, particularly in tropical and subtropical regions. No effective vaccine or antiviral therapies against Dengue virus (DENV) infection are available. Therefore, there is a strong need to develop safe and effective therapeutic strategies that can reduce the burden and duration of hospitalizations due to this life-threatening disease. Oligonucleotide-based strategies are considered as an attractive means of inhibiting viral replication since oligonucleotides can be designed to interact with any viral RNA, provided its sequence is known. The resultant targeted destruction of viral RNA interferes with viral replication without inducing any adverse effects on cellular processes. In this review, we elaborate the ribozymes, RNA interference, CRISPR, aptamer and morpholino strategies for the inhibition of DENV replication and discuss the challenges involved in utilizing such approaches.

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Current Approaches to Drug Discovery for Chagas Disease: Methodological Advances

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207322666191010144111 ◽

2019 ◽

Vol 22 (8) ◽

pp. 509-520

Author(s):

Cauê B. Scarim ◽

Chung M. Chin

Keyword(s):

Drug Discovery ◽

Chagas Disease ◽

Drug Candidates ◽

Lead Compounds ◽

New Drug ◽

Compound Libraries ◽

Screening Assays ◽

Cruzi Infection

Background: In recent years, there has been an improvement in the in vitro and in vivo methodology for the screening of anti-chagasic compounds. Millions of compounds can now have their activity evaluated (in large compound libraries) by means of high throughput in vitro screening assays. Objective: Current approaches to drug discovery for Chagas disease. Method: This review article examines the contribution of these methodological advances in medicinal chemistry in the last four years, focusing on Trypanosoma cruzi infection, obtained from the PubMed, Web of Science, and Scopus databases. Results: Here, we have shown that the promise is increasing each year for more lead compounds for the development of a new drug against Chagas disease. Conclusion: There is increased optimism among those working with the objective to find new drug candidates for optimal treatments against Chagas disease.

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An experimental and theoretical approach to understand Fever, DENF & its cure

Infectious Disorders - Drug Targets ◽

10.2174/1871526520999200905122052 ◽

2020 ◽

Vol 20 ◽

Author(s):

Vijay Kumar Vishvakarma ◽

Ramesh Chandra ◽

Prashant Singh

Keyword(s):

Catalytic Activity ◽

Dengue Virus ◽

Theoretical Approach ◽

Major Part ◽

Genomic Structure ◽

Denv Infection ◽

Structural Proteins ◽

Experimental Approaches ◽

Ns3 Protease ◽

Prime Target

: Fever is a response of human body due to an increase the temperature against the certain stimuli. It may be associated with several reasons and one of the major causes of fever is mosquito bite. Fever due to dengue virus (DENV) infection is being paid most attention out of several other fevers because of a large number of deaths reported worldwide. Dengue virus is transmitted by biting of the mosquitoes, Aedes aegypti and Aedes albopictus. DENV1, DENV2, DENV3 and DENV4 are the four serotypes of dengue virus and these serotypes have 65% similarities in their genomic structure. Genome of DENV is composed of single stranded RNA and it encodes for the polyprotein. Structural and non-structural proteins (nsP) are the two major part of protese. Researchers have paid high attention on the non-structural protease (nsP) of DENV like nsP1, nsP2A, nsP2B, nsP3, nsP4A, nsP4B and nsP5. The NS2B-NS3 protease of DENV is the prime target of the researchers as it is responsible for the catalytic activity. In the present time, Dengvaxia (vaccine) is being recommended to the patients suffering severely due to DENV infection in few countries only. Till date, neither a vaccine nor an effective medicine is available to combat with all four serotypes. This review describes the fever, its causes and studies to cure the infection due to DENV using theoretical and experimental approaches.

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Potential Phosphorylation of Viral Nonstructural Protein 1 in Dengue Virus Infection

Viruses ◽

10.3390/v13071393 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1393

Author(s):

Thanyaporn Dechtawewat ◽

Sittiruk Roytrakul ◽

Yodying Yingchutrakul ◽

Sawanya Charoenlappanit ◽

Bunpote Siridechadilok ◽

...

Keyword(s):

Dengue Virus ◽

Nonstructural Protein ◽

Antiviral Drug ◽

Denv Infection ◽

Site Directed Mutagenesis ◽

Phosphorylation Sites ◽

Post Translational Modification ◽

Multifunctional Protein ◽

Nonstructural Protein 1 ◽

Underlying Mechanisms

Dengue virus (DENV) infection causes a spectrum of dengue diseases that have unclear underlying mechanisms. Nonstructural protein 1 (NS1) is a multifunctional protein of DENV that is involved in DENV infection and dengue pathogenesis. This study investigated the potential post-translational modification of DENV NS1 by phosphorylation following DENV infection. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), 24 potential phosphorylation sites were identified in both cell-associated and extracellular NS1 proteins from three different cell lines infected with DENV. Cell-free kinase assays also demonstrated kinase activity in purified preparations of DENV NS1 proteins. Further studies were conducted to determine the roles of specific phosphorylation sites on NS1 proteins by site-directed mutagenesis with alanine substitution. The T27A and Y32A mutations had a deleterious effect on DENV infectivity. The T29A, T230A, and S233A mutations significantly decreased the production of infectious DENV but did not affect relative levels of intracellular DENV NS1 expression or NS1 secretion. Only the T230A mutation led to a significant reduction of detectable DENV NS1 dimers in virus-infected cells; however, none of the mutations interfered with DENV NS1 oligomeric formation. These findings highlight the importance of DENV NS1 phosphorylation that may pave the way for future target-specific antiviral drug design.

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Poxviral Strategies to Overcome Host Cell Apoptosis

Pathogens ◽

10.3390/pathogens10010006 ◽

2020 ◽

Vol 10 (1) ◽

pp. 6

Author(s):

Chathura D. Suraweera ◽

Mark G. Hinds ◽

Marc Kvansakul

Keyword(s):

Viral Infections ◽

B Cell Lymphoma ◽

Intrinsic Apoptosis ◽

Host Cell Apoptosis ◽

Successful Infection ◽

Infected Cells ◽

Host Virus Interactions ◽

Almost All ◽

Virus Interactions ◽

Multicellular Organisms

Apoptosis is a form of cellular suicide initiated either via extracellular (extrinsic apoptosis) or intracellular (intrinsic apoptosis) cues. This form of programmed cell death plays a crucial role in development and tissue homeostasis in multicellular organisms and its dysregulation is an underlying cause for many diseases. Intrinsic apoptosis is regulated by members of the evolutionarily conserved B-cell lymphoma-2 (Bcl-2) family, a family that consists of pro- and anti-apoptotic members. Bcl-2 genes have also been assimilated by numerous viruses including pox viruses, in particular the sub-family of chordopoxviridae, a group of viruses known to infect almost all vertebrates. The viral Bcl-2 proteins are virulence factors and aid the evasion of host immune defenses by mimicking the activity of their cellular counterparts. Viral Bcl-2 genes have proved essential for the survival of virus infected cells and structural studies have shown that though they often share very little sequence identity with their cellular counterparts, they have near-identical 3D structures. However, their mechanisms of action are varied. In this review, we examine the structural biology, molecular interactions, and detailed mechanism of action of poxvirus encoded apoptosis inhibitors and how they impact on host–virus interactions to ultimately enable successful infection and propagation of viral infections.

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