Effects of the Natural Flavonoid Quercetin on Arenavirus Junín Infection.

There is no specific chemotherapy approved for the treatment of pathogenic arenaviruses that cause severe hemorrhagic fever (HF) in the population of endemic regions in America and Africa. The present study reports the effects of the natural flavonoid quercetin (QUER) on the infection of A549 and Vero cells with Junín virus (JUNV), agent of the Argentine HF. By infectivity assays, a very effective dose-dependent reduction of JUNV multiplication was shown by cell pretreatment at 2-6 h prior to the infection at non-cytotoxic concentrations, with 50% effective concentration values in the range of 6.

Modulation of the Aryl Hydrocarbon Receptor Signaling Pathway Impacts on Junín Virus Replication.

Junín virus (JUNV), a member of the family , is the etiological agent of the Argentine hemorrhagic fever, an endemic disease in the rural region of Argentina lacking a specific chemotherapy. Aryl hydrocarbon receptor (AHR) is expressed in several mammalian tissues and has been indicated as a sensor of ligands from variable sources and a modulator of the cell immune response. Interestingly, recent studies have suggested that the activation or depression of the AHR signaling pathway may play a role in the outcome of diverse human viral infections.

Inhibitors of Nucleotide Biosynthesis as Candidates for a Wide Spectrum of Antiviral Chemotherapy.

Emerging and re-emerging viruses have been a challenge in public health in recent decades. Host-targeted antivirals (HTA) directed at cellular molecules or pathways involved in virus multiplication represent an interesting strategy to combat viruses presently lacking effective chemotherapy. HTA could provide a wide range of agents with inhibitory activity against current and future viruses that share similar host requirements and reduce the possible selection of antiviral-resistant variants.

Antiviral activity against Zika virus of a new formulation of curcumin in poly lactic-co-glycolic acid nanoparticles.

Objectives: In the search of an effective antiviral formulation, the natural product curcumin (CUR) was encapsulated into poly(lactic-co-glycolic acid) nanoparticles, a non-toxic bioresorbable and biocompatible copolymer. The resulting CUR containing particles (PLGA-CUR NPs) were characterized and analysed for antiviral activity against Zika virus (ZIKV) infection.

Methods: The PLGA-CUR NPs were characterized by Fourier transform infrared, differential scanning calorimetry, dynamic light scattering, scanning electron microscopy and thermogravimetric analysis and release profile.

Imidazo[2,1-b]thiazole carbohydrate derivatives: Synthesis and antiviral activity against Junin virus, agent of Argentine hemorrhagic fever.

Herein, we describe the syntheses of 3,5-disubstituted imidazo[2,1-b]thiazole. The cyclization step was performed in two different conditions by using either thermal or microwave heating. Comparing the results of both methodologies, we found that the microwave assistance is an improved alternative to obtain this family of heterocyclic compound.

Xylans from Scinaia hatei: Structural features, sulfation and anti-HSV activity.

Natural compounds offer interesting pharmacological perspectives for antiviral drug development with regard to broad-spectrum antiviral properties and novel modes of action. In this study, we have analyzed alkali-extracted xylan of Scinaia hatei. Alkali extraction of this red alga yielded a xylan shown to have a molecular mass of 120kDa and a linear structure of (1-->4)-linked beta-d-xylopyranosyl residues.

Sulfated xylomannans from the red seaweed Sebdenia polydactyla: structural features, chemical modification and antiviral activity.

Background: Many viruses display affinity for cell surface heparan sulfate proteoglycans with biological relevance in virus entry. This raises the possibility of the application of sulfated polysaccharides in antiviral therapy.

Methods: In this study, we analysed polysaccharide fractions isolated from Sebdenia polydactyla.

Structural features and antiviral activity of sulphated fucans from the brown seaweed Cystoseira indica.

Natural compounds offer interesting pharmacological perspectives for antiviral drug development. In this study, we have analysed sulphated-fucan-containing fractions isolated from the brown seaweed Cystoseira indica. The crude water extract (CiWE) and the main fraction (CiF3) obtained by anion exchange chromatography had potent antiviral activity against herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) without cytotoxicity for Vero cell cultures.