For centuries, food, herbal medicines, and natural products have been valuable resources for discovering novel antiviral drugs, uncovering new structure-activity relationships, and developing effective strategies to prevent/treat viral infections. One such resource is Phellinus linteus, a mushroom used in folk medicine in Taiwan, Japan, Korea, and China. In this rich historical context, the key metabolites of Phellinus linteus mycelia ethanolic extract (GKPL) impacting the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at multiple stages have yet to be explored.
View Article and Find Full Text PDFDengue virus (DENV) is a cause of vascular endothelial dysfunction and vascular leakage, which are characterized as hallmarks of dengue hemorrhagic fever or dengue shock syndrome, which become a severe global health emergency with substantial morbidity and mortality. Currently, there are still no promising therapeutics to alleviate the dengue-associated vascular hemorrhage in a clinical setting. In the present study, we first observed that heme oxygenase-1 (HO-1) expression level was highly suppressed in severe DENV-infected patients.
View Article and Find Full Text PDFDengue virus (DENV) caused millions of infections around the world annually. Co-infection with different serotypes of DENV is associated with dengue hemorrhagic shock syndrome, leading to an estimate of 50% death rate. No approved therapies are currently available for the treatment of DENV infection.
View Article and Find Full Text PDFBackground: Dengue virus (DENV), a common and widely spread arbovirus, causes life-threatening diseases, such as dengue hemorrhagic fever or dengue shock syndrome. There is currently no effective therapeutic or preventive treatment for DENV infection.
Methods: Next-generation sequencing analysis revealed that prostasin expression was decreased upon DENV infection.
Synthesis and anti-hepatitis C virus (anti-HCV) effects of certain 3-amino-2-hydroxy-propoxy isoflavone derivatives, ⁻, were described. The known 3-(3,4-dimethoxyphenyl)-7-(oxiran-2-ylmethoxy)-4-chromen-4-one () was reacted with substituted amines to give the desired isoflavone derivatives, ⁻. Among them, 7-{3-[(3,4-dimethoxy-phenethyl)amino]-2-hydroxypropoxy}-3-(3,4-dimethoxyphenyl)-4-chromen-4-one () was the most active, exhibiting approximately 2-fold higher anti-HCV effects than standard antiviral drug ribavirin (EC of 6.
View Article and Find Full Text PDFBackground: Zika virus (ZIKV) infection causes diseases ranging from acute self-limiting febrile illness to life-threatening Guillain-Barré Syndrome and other neurological disorders in adults. Cumulative evidence suggests an association between ZIKV infection and microcephaly in newborn infants. Given the host-range restrictions of the virus, a susceptible animal model infected by ZIKV must be developed for evaluation of vaccines and antivirals.
View Article and Find Full Text PDFHepatitis C virus (HCV) chronically infects 2-3% people of the global population, which leads to liver cirrhosis and hepatocellular carcinoma. Drug resistance remains a serious problem that limits the effectiveness of US Food and Drug Administration (FDA)-approved direct-acting antiviral (DAA) drugs against HCV proteins. The objective of our study was to discover new antivirals from natural products to supplement current therapeutics.
View Article and Find Full Text PDFDengue virus (DENV) infection causes life-threatening diseases such as dengue hemorrhagic fever and dengue shock syndrome. Currently, there is no effective therapeutic agent or vaccine against DENV infection; hence, there is an urgent need to discover anti-DENV agents. The potential therapeutic efficacy of lucidone was first evaluated in vivo using a DENV-infected Institute of Cancer Research (ICR) suckling mouse model by monitoring body weight, clinical score, survival rate, and viral titer.
View Article and Find Full Text PDFA number of naphtho[1,2-d]oxazole derivatives were synthesized and evaluated for their anti-HCV virus activity. Among them, compound 18 was the most active, exhibited approximately 21-folds more active anti-HCV activity (IC of 0.63 μM) than that of ribavirin (IC = 13.
View Article and Find Full Text PDFA number of diarylpyrazolylquinoline derivatives were synthesized and evaluated for their anti-dengue virus (DENV) activity. Among them, 6-fluoro-2-(1-(4-fluorophenyl)-3- (4-methoxyphenyl)-1H-pyrazol-5-yl)quinoline (11c), 2-[1,3-bis(4-methoxyphenyl)-1H-pyrazol- 5-yl]-6-fluoroquinoline (12c), and 4-[5-(6-fluoroquinolin-2-yl)-3-(4-methoxyphenyl)-1H-pyrazol- 1-yl]benzenesulfonamide (13c) exhibited approximately 10-folds more active anti-DENV-2 activity (IC of 1.36, 1.
View Article and Find Full Text PDFBackground And Purpose: Celastrol, a quinone methide triterpene isolated from the root extracts of Tripterygium wilfordii, can greatly induce the gene expression activity of heme oxygenase-1 (HO-1) to achieve disease prevention and control. HO-1 induction was recently shown to result in anti-HCV activity by inducing type I interferon and inhibiting hepatitis C virus (HCV) NS3/4A protease activity. The aim of the present study is to evaluate the anti-HCV activity of celastrol and characterize its mechanism of inhibition.
View Article and Find Full Text PDFThe strong immunogenicity induction is the powerful weapon to prevent the virus infections. This study demonstrated that one-step synthesis of DNA polyplex vaccine in microneedle (MN) patches can induce high immunogenicity through intradermal vaccination and increase the vaccine stability for storage outside the cold chain. More negative charged DNA vaccine was entrapped into the needle region of MNs followed by DNA polyplex formation with branched polyethylenimine (bPEI) pre-coated in the cavities of polydimethylsiloxane (PDMS) molds that can deliver more DNA vaccine to immune-cell rich epidermis with high transfection efficiency.
View Article and Find Full Text PDFDengue virus (DENV) infects 400 million people worldwide annually. Infection of more than one serotype of DENV highly corresponds to dengue hemorrhagic fever and dengue shock syndrome, which are the leading causes of high mortality. Due to lack of effective vaccines and unavailable therapies against DENV, discovery of anti-DENV agents is urgently needed.
View Article and Find Full Text PDFCyclooxygenase-2 (COX-2) is one of the important mediators of inflammation in response to viral infection, and it contributes to viral replication, for example, cytomegalovirus or hepatitis C virus replication. The role of COX-2 in dengue virus (DENV) replication remains unclear. In the present study, we observed an increased level of COX-2 in patients with dengue fever compared with healthy donors.
View Article and Find Full Text PDFHepatitis C virus (HCV) infection is a causative factor leading to hepatocellular carcinoma due to chronic inflammation and cirrhosis. The aim of the study was first to explore the effects of grape seed extract (GSE) in HCV replication, and then to study mechanisms. The results indicated that a GSE treatment showed significant anti-HCV activity and suppressed HCV-elevated cyclooxygenase-2 (COX-2) expression.
View Article and Find Full Text PDFEthnopharmacological Relevance And Aim Of The Study: Tripterygium wilfordii (lei gong teng; Thunder of God Vine), a member of the Celastraceae family, is a medicinal plant used to treat a range of illnesses. Celastrol is a quinone methide triterpene and the most abundant bioactive constituent isolated from the root extracts of T. wilfordii.
View Article and Find Full Text PDFDengue virus (DENV) infection and replication induces oxidative stress, which further contributes to the progression and pathogenesis of the DENV infection. Modulation of host antioxidant molecules may be a useful strategy for interfering with DENV replication. In this study, we showed that induction or exogenous overexpression of heme oxygenase-1 (HO-1), an antioxidant enzyme, effectively inhibited DENV replication in DENV-infected Huh-7 cells.
View Article and Find Full Text PDFTwo new compounds, 4,10-dihydroxy-11-methyl-dodec-2-en-1,4-olide () (butyrolactone-type) and cyclo-(4--6-dihydroxy-proline-D-leucine) () (diketopiperazine-type), as well as one known 4,10-dihydroxy-10-methyl-dodec-2-en-1,4-olide () and three known diketopiperazines, cyclo-(L-proline-L-leucine) (), cyclo-(4--hydroxy-L-proline-L-leucine) (), and cyclo-(4--hydroxy-L-proline-L-phenylalanine) (), were isolated from the ethyl acetate extracts of GT and C-03. Compounds , and exhibited a significant reduction effect on dengue virus type 2 replication with EC values of 21.2, 16.
View Article and Find Full Text PDFChronic hepatitis C virus (HCV) infection leads to intrahepatic inflammation and liver cell injury, which are considered a risk factor for virus-associated hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. Inflammatory cytokines are critical components of the immune system and influence cellular signaling, and genetic imbalances. In this study, we found that cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) were significantly induced by HCV infection and HCV NS5A expression, and induction of COX-2 correlated with HCV-induced IL-8 production.
View Article and Find Full Text PDFBackground And Purpose: This study was designed to evaluate the effect of betulinic acid (BA), extracted from Avicennia marina, on the replication of hepatitis C virus (HCV) and to investigate the mechanism of this BA-mediated anti-HCV activity.
Experimental Approach: HCV replicon and infectious systems were used to evaluate the anti-HCV activity of BA. Exogenous COX-2 or knock-down of COX-2 expression was used to investigate the role of COX-2 in the anti-HCV activity of BA.
Two novel meroterpenoids, yaminterritrems A (1) and B (2), were isolated from Aspergillus terreus collected from hot spring zones in Yang-Ming Mountain, Taiwan, and cultured at 40 °C. The structures of 1 and 2 were elucidated by NMR, MS spectral and X-ray crystallographic analyses. The biosynthetic route for 1 and 2 involving the conversion of the sesquiterpene with phenyl-α-pyrone is proposed.
View Article and Find Full Text PDFDengue virus (DENV) is a severe mosquito-borne viral pathogen. Neither vaccines nor antiviral therapy is currently available to treat DENV infection. Nucleoside inhibitors targeting viral polymerase have proved promising for the development of drugs against viruses.
View Article and Find Full Text PDFA number of 2-aroyl-3-arylquinoline derivatives was synthesized and evaluated for their anti-Dengue virus activity. Both 2-(hydroxyphenylmethyl)-3-(4-methoxyphenyl)quinoline (13a) and 2-(4-hydroxybenzoyl)-3-(4-hydroxyphenyl)quinoline (17) were found to significantly inhibit the DENV2 RNA expression in Huh-7-DV-Fluc cells with a potency approximately equal to that of ribavirin and the inhibition is in a dose-dependent manner. Compounds 13a and 17 reduced DENV replication in both viral protein and mRNA levels, and no significant cell cytotoxicity was detected, with greater than 50% viability of Huh-7-DV-Fluc cells at a concentration of 100 μM.
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