Inhibition Of Dengue Virus Replication Research Articles

In Silico Analysis of Inhibitor Potential of Punicalagin Compound in Pomegranate (Punica granatum) Against NS5 DENV-3 Protein

Indonesia is one of the Dengue Virus (DENV) endemic areas which are dominated by DENV-2 and DENV-3. Until now, no specific drug therapy has been found to cure Dengue Virus Infection (DVI). Punicalagin is one of the active compounds that have the potential to be used as an antiviral. Unfortunately, not many studies have used punicalagin as a DENV antivirus. This study aims to determine the inhibitory potential of punicalagin compounds against NS5 DENV-3 protein through molecular docking. Molecular docking was performed using AutoDock Tools, ChemDraw, and Discovery Studio Visualizer. The target protein used is NS5 DENV-3 protein with PDB ID code: 4V0Q. The ribavirin compound was used as a positive control. The results obtained show that the punicalagin compound has the ability to attach to target receptors in the C-Terminal domain complex. This docking produces a bond free energy (ΔG) of -6.39 kcal/mol. This result is better than the ΔG of the control compound. Punicalagin's Inhibition Constant (Ki) value also showed better results than ribavirin. So it can be seen that the compound punicalagin effectively inhibits DENV replication and has the potential as a DENV drug candidate.

Antiviral Activity of Catechin against Dengue Virus Infection.

Dengue virus (DENV) is the cause of dengue fever, infecting 390 million people worldwide per year. It is transmitted to humans through the bites of mosquitoes and could potentially develop severe symptoms. In spite of the rising social and economic impact inflicted by the disease on the global population, a conspicuous lack of efficacious therapeutics against DENV still persists. In this study, catechin, a natural polyphenol compound, was evaluated as a DENV infection inhibitor in vitro. Through time-course studies, catechin was shown to inhibit a post-entry stage of the DENV replication cycle. Further investigation revealed its role in affecting viral protein translation. Catechin inhibited the replication of all four DENV serotypes and chikungunya virus (CHIKV). Together, these results demonstrate the ability of catechin to inhibit DENV replication, hinting at its potential to be used as a starting scaffold for further development of antivirals against DENV infection.

Host factor DUSP5 potently inhibits dengue virus infection by modulating cytoskeleton rearrangement

Cytoskeleton has been reported to play an essential role in facilitating the viral life cycle. However, whether the host can exert its antiviral effects by modulating the cytoskeleton is not fully understood. In this study, we identified that host factor DUSP5 was upregulated after dengue virus (DENV) infection. In addition, we demonstrated that overexpression of DUSP5 remarkably inhibited DENV replication. Conversely, the depletion of DUSP5 led to an increase in viral replication. Moreover, DUSP5 was found to restrain viral entry into host cells by suppressing F-actin rearrangement via negatively regulating the ERK-MLCK-Myosin IIB signaling axis. Depletion of dephosphorylase activity of DUSP5 abolished its above inhibitory effects. Furthermore, we also revealed that DUSP5 exhibited broad-spectrum antiviral effects against DENV and Zika virus. Taken together, our studies identified DUSP5 as a key host defense factor against viral infection and uncovered an intriguing mechanism by which the host exerts its antiviral effects through targeting cytoskeleton rearrangement.

A Review on Unleashing the Potentials of Natural Products in Managing Dengue

Background/Aims: Dengue virus (DENV) spreads widely in many tropical and sub-tropical countries by Aedes sp. In recent decades, dengue has been alarmingly on the rise and affects approximately half of the world population. The current dengue treatments are still mainly supportive without any approved vaccines or effective anti-dengue drugs. This leads to an urgency to seek alternative solutions in reducing dengue morbidity and mortality. Methods: A total of 94 articles describing in vitro and in vivo studies were screened and selected through curated databases. The selected articles underpinned the potentials of natural products as alternative anti-dengue compounds. Results: Those compounds have been employed as larvicide, mosquitocide, mosquito repellents, agents in sticky traps and non-specific interventions for dengue. In this review, their direct and indirect effects on dengue virus replication and dengue diseases were deliberated. Inteestingly, the majority of them demonstrated remarkable anti-inflammatory effects on dengue diseases. Several phytochemical contents such as luteolin, coumarins and geraniin were shown to inhibit DENV replication in vitro. Conclusion: Natural product-based anti-dengue agents are believed to be less costly, easy to derive, biologically effective and less toxic. This review, therefore, aims to provide current updates and insights on the benefits of natural products in preventing, managing and treating dengue.

Dengue Virus Replication Is Associated with Catecholamine Biosynthesis and Metabolism in Hepatocytes.

Previously, the association between the catecholamine biosynthetic enzyme L-Dopa decarboxylase (DDC) and Dengue virus (DV) replication was demonstrated in liver cells and was found to be mediated at least by the interaction between DDC and phosphoinositide 3-kinase (PI3K). Here, we show that biogenic amines production and uptake impede DV replication in hepatocytes and monocytes, while the virus reduces catecholamine biosynthesis, metabolism, and transport. To examine how catecholamine biosynthesis/metabolism influences DV, first, we verified the role of DDC by altering DDC expression. DDC silencing enhanced virus replication, but not translation, attenuated the negative effect of DDC substrates on the virus and reduced the infection related cell death. Then, the role of the downstream steps of the catecholamine biosynthesis/metabolism was analyzed by chemical inhibition of the respective enzymes, application of their substrates and/or their products; moreover, reserpine, the inhibitor of the vesicular monoamine transporter 2 (VMAT2), was used to examine the role of uptake/storage of catecholamines on DV. Apart from the role of each enzyme/transporter, these studies revealed that the dopamine uptake, and not the dopamine-signaling, is responsible for the negative effect on DV. Accordingly, all treatments expected to enhance the accumulation of catecholamines in the cell cytosol suppressed DV replication. This was verified by the use of chemical inducers of catecholamine biosynthesis. Last, the cellular redox alterations due to catecholamine oxidation were not related with the inhibition of DV replication. In turn, DV apart from its negative impact on DDC, inhibits tyrosine hydroxylase, dopamine beta-hydroxylase, monoamine oxidase, and VMAT2 expression.

Cordycepin Inhibits Virus Replication in Dengue Virus-Infected Vero Cells.

Dengue virus (DENV) infection causes mild to severe illness in humans that can lead to fatality in severe cases. Currently, no specific drug is available for the treatment of DENV infection. Thus, the development of an anti-DENV drug is urgently required. Cordycepin (3′-deoxyadenosine), which is a major bioactive compound in Cordyceps (ascomycete) fungus that has been used for centuries in Chinese traditional medicine, was reported to exhibit antiviral activity. However, the anti-DENV activity of cordycepin is unknown. We hypothesized that cordycepin exerts anti-DENV activity and that, as an adenosine derivative, it inhibits DENV replication. To test this hypothesis, we investigated the anti-DENV activity of cordycepin in DENV-infected Vero cells. Cordycepin treatment significantly decreased DENV protein at a half-maximal effective concentration (EC50) of 26.94 μM. Moreover, DENV RNA was dramatically decreased in cordycepin-treated Vero cells, indicating its effectiveness in inhibiting viral RNA replication. Via in silico molecular docking, the binding of cordycepin to DENV non-structural protein 5 (NS5), which is an important enzyme for RNA synthesis, at both the methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) domains, was predicted. The results of this study demonstrate that cordycepin is able to inhibit DENV replication, which portends its potential as an anti-dengue therapy.

Computational-aided design: minimal peptide sequence to block dengue virus transmission into cells

Dengue virus (DV) infection is one of the main public health concerns, affecting approximately 390 million people worldwide, as reported by the World Health Organization. Yet, there is no antiviral treatment for DV infection. Therefore, the development of potent and nontoxic anti-DV, as a complement for the existing treatment strategies, is urgently needed. Herein, we investigate a series of small peptides inhibitors of DV antiviral activity targeting the entry process as the promising strategy to block DV infection. The peptides were designed based on our previously reported peptide sequence, DN58opt (TWWCFYFCRRHHPFWFFYRHN), to identify minimal effective inhibitory sequence through molecular docking and dynamics studies. The in silico designed peptides were synthesized using conventional Fmoc solid-phase peptide synthesis chemistry, purified by RP-HPLC and characterized using LCMS. Later, they were screened for their antiviral activity. One of the peptides, AC 001, was able to reduce about 40% of DV plaque formation. This observation correlates well with the molecular mechanics-Poisson–Boltzmann surface area (MM-PBSA) analysis – AC 001 showed the most favorable binding affinity through 60 ns simulations. Pairwise residue decomposition analysis has revealed four key residues that contributed to the binding of these peptides into the DV2 E protein pocket. This work identifies the minimal peptide sequence required to inhibit DV replication and explains the behavior observed on an atomic level using computational study. Communicated by Ramaswamy H. Sarma

Mosquito-infecting virus Espirito Santo virus inhibits replication and spread of dengue virus.

The primary vector of dengue virus (DENV) is Aedes aegypti. The mosquito-infecting virus, Espirito Santo virus (ESV), does not infect Vero (mammalian) cells and grows in mosquito (C6/36) cells without cytopathic effects. Effects of ESV infection on replication of DENV were explored in vitro and in vivo, analyzing protein, RNA genome expression, and plaque formation. ESV and DENV simultaneous coinfection did not block protein synthesis from either virus but did result in inhibition of DENV replication in mosquito cells. Furthermore, ESV superinfected with DENV resulted in inhibition of DENV replication and spread in A. aegypti, thus reducing vector competence. Tissue culture experiments on viral kinetics of ESV and DENV coinfection showed that neither virus significantly affects the replication of the other in Vero, HeLa, or HEK cells. Hence, ESV blocks DENV replication in insect cells, but not the mammalian cells evaluated here. Our study provides new insights into ESV-induced suppression of DENV, a globally important pathogen impacting public health.

A Proposal of Early Diagnosis and Early Management in Dengue Infection and Possible COVID-19

Dengue infection may lead to various sequels, such as undifferentiated fever, dengue fever, or dengue hemorrhagic fever, progressive illness, and death. It also causes significant economic burden associated with healthcare costs and loss of labor. Usually, the treatment of dengue infection is supportive therapy and not a specific treatment, while it is often clinically difficult to predict whether dengue-infected patients will progress to severe disease or not. We propose integrated management strategies for early dengue virus infection based on our 5-year experience in early management of dengue infection, literature reviews, and research studies (over the last 10 years). This proposal consists of 4 aspects: (1) rehydration with oral rehydration therapy; (2) reduction of the proinflammatory cytokines, including tumor necrosis factor-α and interleukin-6 with oral cytokine inhibitors (i.e. pentoxifylline and doxycycline); (3) inhibition of dengue virus replication, viral load reduction, nonstructural protein 1 antigen clearance with doxycycline and ivermectin; and (4) restoration of the immune function by vitamin D and zinc supplementation. The major benefit of these drugs and supplements is that they are already approved by regulatory bodies, affordable, and clinically safe. They result in better clinical and laboratory outcomes, including reductions in hospitalization and cost of treatment. Another benefit is that this strategy may be used for other virus-induced hypercytokinemia, such as coronavirus disease and Ebola.

Cyclovirobuxine D inhibits dengue virus replication by impeding the complete autophagy in a cholesterol-dependent manner

Dengue virus (DENV) is the most common mosquito-borne flavivirus, and it affects millions of people globally every year. Currently, there are no approved drugs for the treatment of dengue infection. By screening a natural product library, we identified a novel compound, cyclovirobuxine D (Cvb D), that displays anti-DENV activity. Cvb D inhibits DENV replication in vitro in a dose-dependent manner and protects suckling mice against lethal DENV infection. Mechanistically, Cvb D regulates the expression of genes related to the cellular cholesterol pathway. As a result, Cvb D increases cellular cholesterol synthesis and accumulation, activates mTOR, and inhibits viral-dependent autophagy. Cvb D does not suppress autophagy initiation but impedes the nuclear translocation of the lysosome transcription factor TFEB. In addition, Cvb D restricts the replication of other positive-strand RNA viruses such as Zika virus and Coxsackievirus B3. We speculate that Cvb D could be a broad-spectrum antiviral drug candidate for use against positive-strand RNA viruses that require autophagy for optimal replication.

Crocetin Improves Dengue Virus-Induced Liver Injury

Dengue virus (DENV) infection is one of the most widespread mosquito-borne viral infections. Liver injury is commonly observed in severe DENV infection, and the present study aimed to examine the efficacy of crocetin treatment in an immunocompetent mouse model of DENV infection exhibiting liver injury. The efficacy of crocetin treatment in DENV-induced liver injury was assessed via both transaminase levels and histopathology analysis. A real-time polymerase chain reaction array was then used to describe the expression of 84 apoptosis-related genes. Using real-time RT-PCR and Western blot analysis, the gene expressions of host factors were investigated. Additionally, the effect of crocetin in NF-kB signaling during DENV infection was studied. We did not observe any significant reduction in virus production when DENV-infected mice were treated with crocetin. However, DENV-infected mice treated with crocetin showed reduced DENV-induced apoptosis. The real-time polymerase chain reaction array revealed pro-inflammatory cytokine expressions to be significantly reduced in the crocetin-treated DENV-infected mice. We also found that crocetin could effectively modulate antioxidant status in DENV-infected mice. Moreover, crocetin demonstrated the ability to reduce the nuclear translocation of NF-kB in DENV-infected mice. Our results suggest that crocetin treatment does not inhibit DENV replication in the liver of DENV-infected mice; however, we did find that crocetin improves host responses that reduce liver injury.

Early Diagnosis and Early Management Proposal in Dengue Infection: New Normal to Applied Strategy for COVID-19 Infection

Dengue infection may lead to various sequels, such as undifferentiated fever (UF), dengue fever (DF), or dengue hemorrhagic fever (DHF), progressive illness, and death. It also causes significant economic burdens that are associated with health-care costs and loss of labor. Usually, the treatment of dengue infection is supportive therapy and not the specific treatment for it, while it is often clinically difficult to predict whether dengue-infected patients will progress to severe diseases or not. We here propose integrated management strategies for early dengue virus (DENV) infection based on our 5-year experience in early management of dengue infection, literature reviews, and research studies over the last 10 years. This proposal consists of 4 aspects: (1) rehydration with oral rehydration therapy, (2) reduction of the pro-inflammatory cytokines, including TNF-α and IL-6 with oral cytokine inhibitors i.e., pentoxifylline and doxycycline, (3) inhibition of DENV replication, viral load reduction, nonstructural protein 1 antigen (NS1Ag) clearance with doxycycline and ivermectin, (4) restoration of the immune function with vitamin D and zinc supplementation. The major benefit of these drugs and supplements is that they are already approved by regulatory bodies, affordable, and clinically safe. They result in better clinical and laboratory outcomes, including in a reduction in hospitalization and cost of treatment. Another benefit is that it may use this strategy for other virus-induced hypercytokinemia such as coronavirus disease (COVID-19) and Ebola.

The E3 Ubiquitin Ligase SIAH1 Targets MyD88 for Proteasomal Degradation During Dengue Virus Infection.

The dengue virus presents a serious threat to human health globally and can cause severe, even life-threatening, illness. Dengue virus (DENV) is endemic on all continents except Antarctica, and it is estimated that more than 100 million people are infected each year. Herein, we further mine the data from a previously described screen for microRNAs (miRNAs) that block flavivirus replication. We use miR-424, a member of the miR-15/16 family, as a tool to further dissect the role of host cell proteins during DENV infection. We observed that miR-424 suppresses expression of the E3 ubiquitin ligase SIAH1, which is normally induced during dengue virus 2 (DENV2) infection through activation of the unfolded protein response (UPR). Specific siRNA-mediated knockdown of SIAH1 also results in inhibition of DENV replication, demonstrating that this target is at least partly responsible for the antiviral activity of miR-424. We further show that SIAH1 binds to and ubiquitinates the innate immune adaptor protein MyD88 and that the antiviral effect of SIAH1 knockdown is reduced in cells in which MyD88 has been deleted by CRISPR/Cas9 gene editing. Additionally, MyD88-dependent signaling, triggered either by DENV2 infection or the Toll-like receptor 7 (TLR7) ligand imiquimod, is increased in cells in which SIAH1 has been knocked down by miR-424 or a SIAH1-specific siRNA. These observations suggest an additional pathway by which DENV2 harnesses aspects of the UPR to dampen the host innate immune response and promote viral replication.

Inhibition of N-myristoyltransferase1 affects dengue virus replication.

Dengue virus (DENV) causes dengue fever, a self‐limiting disease that could be fatal due to serious complications. No specific treatment is currently available and the preventative vaccine is only partially protective. To develop a potential drug target for dengue fever, we need to understand its biology and pathogenesis thoroughly. N‐myristoyltransferase (NMT) is an N‐terminal protein lipidation enzyme that catalyzes the covalent cotranslational attachment of fatty acids to the amino‐terminal glycine residue of a number of proteins, leading to the modulation of various signaling molecules. In this study, we investigated the interaction of dengue viral proteins with host NMT and its subsequent effect on DENV. Our bioinformatics, molecular docking, and far‐western blotting analyses demonstrated the interaction of viral envelope protein (E) with NMT. The gene expression of NMT was strongly elevated in a dependent manner during the viral replication phase in dendritic cells. Moreover, NMT gene silencing significantly inhibited DENV replication in dendritic cells. Further studies investigating the target cell types of other host factors are suggested.

Antiviral Activity of Isobutyl Gallate to Dengue Virus Serotype 2 In Vitro

Dengue is one of the most prevalent mosquito-borne diseases in Indonesia that lead to a spectrum of disease, ranging from a flu-like illness to a life-threatening dengue shock syndrome. Despite its high incidence and mortality rate, there is currently no antiviral drug available against dengue virus (DENV). Therefore, research regarding the development of anti-viral to DENV is essential. The aim of this study was to evaluate the antiviral activity of isobutyl gallate, a gallic acid derivative, against DENV in vitro. Various concentration of isobutyl gallate was added to DENV-2 strain New Guinea C (NGC) and infected to Vero cell line. Inhibition of DENV replication as aligned with half inhibitory concentration (IC50) value was determined by focus assay. Furthermore, the toxicity of isobutyl gallate that corresponds with cytotoxic concentration (CC50) value was determined by MTT assay. Selectivity index (SI) value was defined as the ratio of CC50 to IC50. Isobutyl gallate showed no cytotoxic effects against Huh 7 it-1 cells with CC50 values of 167.19 μg/mL and exhibited strong antiviral activity with IC50 of 4.45 μg/mL, hence a significant SI value of 25.69. Isobutyl gallate exerts potent antiviral activity against DENV.

Inhibition of dengue virus replication in monocyte-derived dendritic cells by vivo-morpholino oligomers

Skin dendritic cells (DCs) are primary target cells of dengue virus (DENV) infection and they play an important role in its immunopathogenesis. Monocyte-derived dendritic cells (MDDCs) represent dermal and bloodstream DCs that serve as human primary cells for ex vivo studies of DENV infection. Improved understanding of the mechanisms that effectuate the inhibition of DENV replication in MDDCs will accelerate the development of antiviral drugs to treat DENV infection. In this study, we investigated whether or not vivo-morpholino oligomer (vivo-MO), which was designed to target the top of the 3′ stem-loop (3′ SL) at the 3′ UTR of the DENV genome, could inhibit DENV infection and replication in MDDCs. The findings of this study revealed that vivo-MO-1 could inhibit DENV-2 infection in MDDCs, and that it could significantly reduce DENV RNA, protein, and viral production in a dose-dependent manner. Treatment of MDDCs with 4 μM of vivo-MO-1 decreased DENV production by more than 1,000-fold, when compared to that of the vivo-MO-NC control. Thus, vivo-MO-1 targeting of DENV RNA demonstrates potential for further development into an anti-DENV agent.

An estrogen antagonist, cyclofenil, has anti-dengue-virus activity.

Dengue virus (DENV) infections are a major cause of morbidity and mortality in tropical and subtropical areas. Several compounds that act against DENV have been studied in clinical trials to date; however, there have been no compounds identified that are effective in reducing the severity of the clinical manifestations. To explore anti-DENV drugs, we examined small molecules that interact with DENV NS1 and inhibit DENV replication. Cyclofenil, which is a selective estrogen receptor modulator (SERM) and has been used clinically as an ovulation-inducing drug, showed an inhibitory effect on DENV replication in mammalian cells but not in mosquito cells. Other SERMs also inhibited DENV replication in mammalian cells, but cyclofenil showed the weakest cytotoxicity among these SERMs. Cyclofenil also inhibited the replication of Zika virus. A time-of-addition assay suggested that cyclofenil may interfere with two stages of the DENV life cycle: the translation-RNA synthesis and assembly-maturation stages. However, the level of intracellular infectious particles decreased more drastically after treatment with cyclofenil than the viral RNA level did, indicating that the assembly-maturation stage might be the main target of cyclofenil. In electron microscopy analysis, many aggregated particles were detected in DENV-infected cells in the presence of cyclofenil, supporting the possibility that cyclofenil impedes the process of assembly and maturation of DENV.

Drug repurposing of quinine as antiviral against dengue virus infection

Dengue virus (DENV) disease outbreaks continue to develop across the globe with significant associated mortality and economic burden, yet no treatment has been approved to combat this virus. In an attempt to identify novel drug candidates as therapeutics for DENV infection, we evaluated four US Food and Drug Administration (FDA) approved drugs including aminolevullic acid, azelaic acid, mitoxantrone hydrochloride, and quinine sulfate, and tested their ability to inhibit DENV replication using focus-forming unit assay to quantify virus production. Of the four investigated compounds, quinine was found to have the most pronounced anti-DENV activity. Quinine inhibited DENV production of DENV by about 80% compared to untreated controls, while the other three drugs decreased virus production by only about 50%. Moreover, quinine inhibited DENV production of all four serotypes of DENV. Reduction in virus production was documented in three different cell lines of human origin. Quinine significantly inhibited DENV replication by reducing DENV RNA and viral protein synthesis in a dose-dependent manner. In addition, quinine ameliorated expression of genes related to innate immune response. These findings suggest the efficacy of quinine for stimulating antiviral genes to reduce DENV replication. The antiviral activity of quinine observed in this study may have applicability in the development of new drug therapies against DENV.

Assessment of activity and mechanism of action of β-Dglucan against dengue virus

Purpose : To assess the antiviral efficiency of β-D-glucan (BDG) on human liver cell line (WRL68) infected with dengue virus (DENV). Methods : Cytotoxic activity was assessed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Solid-phase virus binding assay was used to determine the presence of a chemical affinity between dengue virus type 2 (DENV-2) and BDG. Plaque formation assay was performed to measure the suppression of DENV-2. Results : Plaque formation assay results revealed that the inhibition of DENV infection by BDG was effective at 400 μg/mL which occurred by inhibiting virus replication. BDG inhibited DENV replication and produced minimal toxicity on WRL68 cells at 600 μg/mL in a concentration-dependent manner. Treatment of DENV-2 with the highest concentration of the BDG resulted in 60, 55, and 50 % viability at 24, 48, and 72 h, respectively. Plaque formation and binding efficiency data confirmed that BDG protected the WRL68 cells against DENV-2. Conclusion : The results indicate that in infected cells, β-D-glucan was found to be potent in inhibiting replication of the dengue virus. Keywords : Dengue, β-D-glucan, Polysaccharide, Antiviral, Plaque formation, Binding efficiency

Posaconazole inhibits dengue virus replication by targeting oxysterol-binding protein

Dengue virus (DENV) is associated with an estimated 390 million infections per year, occurring across approximately 100 countries in tropical and sub-tropical regions. To date, there are no antiviral drugs or specific therapies to treat DENV infection. Posaconazole and itraconazole are potent antifungal drugs that inhibit ergosterol biosynthesis in fungal cells, but also target a number of human proteins. Here, we show that itraconazole and posaconazole have antiviral activity against DENV. Posaconazole inhibited replication of multiple serotypes of DENV and the related flavivirus Zika virus, and reduced viral RNA replication, but not translation of the viral genome. We used a combination of knockdown and drug sensitization assays to define the molecular target of posaconazole that mediates its antiviral activity. We found that knockdown of oxysterol-binding protein (OSBP) inhibited DENV replication. Moreover, knockdown of OSBP, but not other known targets of posaconazole, enhanced the inhibitory effect of posaconazole. Our findings imply OSBP as a potential target for the development of antiviral compounds against DENV.