Solar UV exposure damages the skin through the photochemical generation of reactive oxygen species, causing an increase in oxidative stress. Polyphenols appear to be particularly promising photoprotective agents, due to their antioxidant and sunscreen properties. In order to assess the photoprotective effects of a new standardised extract of Olea europaea (Opextan®) particularly rich in polyphenols, we performed three separate studies in healthy volunteers. We found that: 1) oral supplementation with Opextan® 400 mg for 28 days significantly reduced (-36.4%) systemic oxidative stress, as measured by urinary levels of 8-isoprostane (PGF2a); 2) Opextan®, applied topically, significantly reduced UV-induced lipid peroxidation (-27.1%) versus placebo; 3) oral supplementation with Opextan® 160 mg for 28 days significantly increased the minimal erythemal dose (+14.5%) and the time to UV exposure (+14.1%) versus placebo. Our observations indicate that Opextan® exerts photoprotective effects thanks to the antioxidant properties of its components, and therefore could be useful in the management of skin conditions associated with increased oxidative stress.
Photoprotective and antioxidant effects of a standardised olive (Olea europaea) extract in healthy volunteers
Conte C.;
2015-01-01
Abstract
Solar UV exposure damages the skin through the photochemical generation of reactive oxygen species, causing an increase in oxidative stress. Polyphenols appear to be particularly promising photoprotective agents, due to their antioxidant and sunscreen properties. In order to assess the photoprotective effects of a new standardised extract of Olea europaea (Opextan®) particularly rich in polyphenols, we performed three separate studies in healthy volunteers. We found that: 1) oral supplementation with Opextan® 400 mg for 28 days significantly reduced (-36.4%) systemic oxidative stress, as measured by urinary levels of 8-isoprostane (PGF2a); 2) Opextan®, applied topically, significantly reduced UV-induced lipid peroxidation (-27.1%) versus placebo; 3) oral supplementation with Opextan® 160 mg for 28 days significantly increased the minimal erythemal dose (+14.5%) and the time to UV exposure (+14.1%) versus placebo. Our observations indicate that Opextan® exerts photoprotective effects thanks to the antioxidant properties of its components, and therefore could be useful in the management of skin conditions associated with increased oxidative stress.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.