Virucidal, antiviral and immunomodulatory activities of β-escin and Aesculus hippocastanum extract

Objectives-Escin, one of the constituents of Aesculus hippocastanum L. (Hippocastanaceae) seed extract (AH), inhibits NF-B activation, which plays an important role in HSV-1 replication. The aim was to examine the antiherpetic activity of -escin and AH, as well as their effect on the activation of NF-B and AP-1 and cytokine secretion in epithelial cells and macrophages. MethodsCell viability was evaluated using MTT assay, and antiviral and virucidal activity was determined by plaque assay. The effect on NF-B and AP-1 signalling pathways activation was determined by a luciferase reporter assay, and cytokine production was measured by ELISA. Key findings-Escin and AH had virucidal and anti-HSV-1 activities, and the antiviral activity was discovered for other enveloped viruses (VSV and Dengue). Moreover, -escin and AH significantly reduced NF-B and AP-1 activation and cytokine production in macrophages stimulated with HSV-1 and TLRs ligands. However, an enhanced activation of these pathways and an increase in the levels of pro-inflammatory cytokines in -escin and AH-treated HSV-1-infected epithelial cells were found. ConclusionsThis study demonstrates virucidal and broad-spectrum antiviral activities for escin and AH. Besides, -escin and AH modulate cytokine production depending on the stimuli (viral or non-viral) and the cell type under study.