Olive leaf phenolics and cardiovascular risk reduction

• Main Author: Lockyer, Stacey
• Published: University of Reading 2014
• Subjects: 616.106
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625435

Olive leaf extract (OLE) contains polyphenols unique to the olive plant (Olea europaea), namely the secoiridoid oleuropein and its derivative hydroxytyrosol (HT). As such, OLE contains a similar phenolic profile to olive oil. Early evidence suggests some beneficial effects of OLE on human health. We conducted a double-blind, controlled, cross over, postprandial study, in which healthy individuals (n=18) consumed OLE capsules containing 58 mg oleuropein and 4 mg HT or a control. Arterial stiffness, measured by Digital Volume Pulse, and the production of inflammatory cytokine interleukin-8 (IL-8), measured in LPS-stimulated whole blood cultures (WBC), were both significantly reduced (p<O.05), across the whole acute intervention period. There were no significant treatment effects on IL-6, IL-I~, tumor necrosis factor-a or IL-l0 production. These effects were paralleled by the appearance of 'oleuropein equivalents', homovanillic alcohol and hydroxytyrosol, major metabolites of OLE, in urine 8-24 hours post consumption.