Oleuropein potently and dose-dependently inhibits copper sulphate-induced oxidation of low-density lipoproteins (LDL) [1, 2]. According to De la Puerta et al. [3], Oleuropein has both the ability to scavenge nitric oxide and to cause an increase in the inducible nitric oxide synthase (iNOS) expression in the cell. A scavenging effect of Oleuropein was demonstrated with respect to hypochlorous acid (HOCl) [1]. HOCl is an oxidative substance produced in vivo by neutrophil myeloperoxidase at the site of inflammation and can cause damage to proteins including enzymes.

Coni et al. [4] conducted a study with laboratory rabbits fed special diets that contained olive oil and Oleuropein. The results indicate that the addition of Oleuropein increases the ability of LDL to resist oxidation and at the same time reduces the plasma levels of total, free, and esterified cholesterol.

Additionally, the potential protective effects of Oleuropein have been investigated in isolated rat hearts by Manna et al. [5]. The organs were subjected to 30 min of no-flow global ischemia and then reperfused. At different intervals, the coronary heart effluent was collected and assayed for creatine kinase activity and reduced and oxidized glutathione. The extent of lipid peroxidation was evaluated by measuring the concentration of thiobarbituric acid-reactive substance in the muscle. According to the authors, the findings of the study strengthen the hypothesis that the health benefits of olive oil are related to the Oleuropein derivatives that are present in olive oil. De la Puerta et al. [6] determined the anti-eicosanoid and antioxidant effects in leukocytes of the principal phenolic compounds (Oleuropein, tyrosol, hydroxytyrosol and caffeic acid) from the polar fraction of olive oil. Moreover, Visioli et al. [7] demonstrated that the administration of catecholic phenolic from olive oil (Oleuropein) dose-dependently decreases the urinary excretion of 8-iso- PGF2α, indicating lower in vivo lipid peroxidation in supplemented volunteers.

• [1] Visioli F, Galli C, Galli G, Caruso D. Biological activities and metabolic fate of olive oil phenols. Eur J Lipid Sci Technol. 2002; 104: 677–684. doi:10.1002/1438-9312(200210)104:9/10<677::AID-EJLT677>3.0.CO;2-M
• [2] Visioli F, Bogani P, Galli C. Healthful properties of olive oil minor components, in Olive Oil, Chemistry and Technology. Boskou D (Ed.). AOCS Press, Champaign, IL: 2006: 173–190.
• [3] De la Puerta R, Dominguez MEM, Ruiz-Guttierrez V, Flavill JA, Hoult JRS. Effects of olive oil phenolics on scavenging of reactive nitrogen species and upon nitrergic neurotransmission. Life Sci. 2001; 69: 1213–1222. doi:10.1016/S0024-3205(01)01218-8
• [4] Coni E, Benedetto R, Pasquale M, Masella R, Modesti D, Mattei R, Carline EA. Protective effect of Oleuropein, an olive oil biophenol, on low density lipoprotein oxidizability in rabbits. Lipids. 2000; 35: 45–54. doi:10.1007/s11745-000-0493-2
• [5] Manna C, Migliardi V, Golino P, Scognmiglio A, Galetti P, Chiariello M, Zappia V. Oleuropein prevents oxidative myocardial injury by ischemia and reperfusion. J Nutr Biochem. 2004; 15: 461–468. doi:10.1016/j.jnutbio.2003.12.010
• [6] De la Puerta R, Guttierrez VR, Hoult JRS. Inhibition of leukocyte 5-lipoxygenase by phenolics from virgin olive oil. Biochem Pharmacol. 1999; 57: 445–449. doi:10.1016/S0006-2952(98)00320-7
• [7] Visioli F, Caruso D, Galli C, Viappiani S, Galli G, Sala A. Olive oil rich in natural catecholic phenols decrease isoprostane excretion in humans. Biochem Biophys Res Commun. 2000; 278: 797–799. doi:10.1006/bbrc.2000.3879
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• Structure-antioxidant Activity Relationship of β-Cyclodextrin Inclusion Complexes With Olive Tyrosol, Hydroxytyrosol and Oleuropein: Deep Insights From X-ray Analysis, DFT Calculation and DPPH Assay
• Oleuropein-Rich Diet Attenuates Hyperglycemia and Impaired Glucose Tolerance in Type 2 Diabetes Model Mouse
• Oleuropein Improves Glucose Tolerance and Lipid Profile in Rats With Simultaneous Renovascular Hypertension and Type 2 Diabetes
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• The Olive Leaf Extract Oleuropein Exerts Protective Effects Against Oxidant-Induced Cell Death, Concurrently Displaying Pro-Oxidant Activity in Human Hepatocarcinoma Cells
• Oleuropein, an Anti-Oxidant Polyphenol Constituent of Olive Promotes α-Secretase Cleavage of the Amyloid Precursor Protein (AβPP)