TNF and endothelial dysfunction: Interestingly, in exploiting the effect of TNF-α as a molecule capable of stimulating mechanisms involved in endothelial dysfunction [29, 30], we have found that in TNF-α-stimulated GD-HUVECs, ovothiol A induced a downregulation of adhesion molecule expression and monocyte-HUVEC interaction, and this effect was associated with a reduction of nitro oxidative species and an increase in NO bioavailability.