Analysis of Antioxidant and Antiviral Effects of Olive (Olea europaea L.) Leaf Extracts and Pure Compound Using Cancer Cell Model

Abstract

The present study aims to assess the antioxidant and antiviral effectiveness of leaf extracts obtained from Olea europaea L. var. sativa and Olea europaea L. var. sylvestris. The total antioxidant activity was determined via both an ammonium phosphomolybdate assay and a nitric oxide radical inhibition assay. Both extracts showed reducing abilities in an in vitro system and in human HeLa cells. Indeed, after oxidative stress induction, we found that exposition to olive leaf extracts protects human HeLa cells from lipid peroxidation and increases the concentration of enzyme antioxidants such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase. Additionally, OESA treatment affects viral DNA accumulation more than OESY, probably due to the exclusive oleuropein content. In fact, subtoxic concentrations of oleuropein inhibit HSV-1 replication, stimulating the phosphorylation of PKR, c-FOS, and c-JUN proteins. These results provide new knowledge about the potential health benefits and mechanisms of action of oleuropein and oleuropein-rich extracts.

3D-Printed Alginate/Pectin-Based Patches Loaded with Olive Leaf Extracts for Wound Healing Applications: Development, Characterization and In Vitro Evaluation of Biological Properties

“…Generally, at an acidic pH, antioxidant species reduce Mo(VI) to Mo(V), resulting in the formation of a green phosphate–Mo(V) complex. The high absorbance of OLEF_9 indicated significant antioxidant activity compared with the literature [ 50 ], being equal to 22.66 ± 0.52 mg CAE/g.…”

Oleuropein activates autophagy to circumvent anti-plasmodial defense

“… 5 , 50 Further, free radical scavenging activity of OLP is shown to exhibit anti-inflammatory and disease-fighting activity. 51 The relative mRNA expression of inflammatory immune mediators in the antigen-stimulated macrophages following the drug treatment in prophylactic and therapeutic mode suggested the attenuation of inflammatory responses. Our data confirming the reduction in the inflammation is consistent to the reports published in human coronary artery endothelial cells (HCAEC) 52 and rodent plasmodia infection.…”

Mechanistic Understanding of the Antiviral Properties of Pistachios and Zeaxanthin against HSV-1

“…Immunoblot analysis was carried out to evaluate the accumulation of viral proteins as previously reported [ 26 ]. Briefly, total cells lysates were prepared from cells by SDS sample buffer 1X (62.5 mM Tris-HCl (Tris(hydroxymethyl) aminomethane hydrochloride) pH 6.8; 50 mM DTT (dithiothreitol); 10% glycerol; 2% SDS (sodium dodecyl sulfate); 0.01% Bromophenol Blue; EDTA-free Protease Inhibitor Cocktail 1X (Roche)), and after they are boiled for 5 min.…”