UV filters, ingredients with a recognized anti-inflammatory effect.

BACKGROUND: To explain observed differences during SPF determination using either an in vivo or in vitro method, we hypothesized on the presence of ingredients having anti-inflammatory properties. METHODOLOGY/PRINCIPAL FINDINGS: To research our hypothesis, we studied the 21 UV filters both available on the market and authorized by European regulations and subjected these filters to the phorbol-myristate-acetate test using mice. We then catalogued the 13 filters demonstrating a significant anti-inflammatory effect with edema inhibition percentages of more than 70%. The filters are: diethylhexyl butamido triazone (92%), benzophenone-5 and titanium dioxide (90%), benzophenone-3 (83%), octocrylène and isoamyl p-methoxycinnamate (82%), PEG-25 PABA and homosalate (80%), octyl triazone and phenylbenzimidazole sulfonic acid (78%), octyl dimethyl PABA (75%), bis-ethylhexyloxyphenol methoxyphenyl triazine and diethylamino hydroxybenzoyl hexylbenzoate (70%). These filters were tested at various concentrations, including their maximum authorized dose. We detected a dose-response relationship. CONCLUSIONS/SIGNIFICANCE: The anti-inflammatory effect of a sunscreen ingredient may affect the in vivo SPF value

Influence de certains corps gras sur le Sun Protection Factor (SPF) mesuré in vitro

In order to improve the knowledge on the influence of vehicle on the SPF (Sun Protection Factor), we determined in vitro the SPF from an oil-in-water (O/W) emulsion containing octylmethoxycinnamate (4%). We changed the oily phase composition. The in vitro determination of SPF is based on the physical determination of the reduction of the energy in the UV range, through a film of product which has previously been spread on an adequate substrate. About 30 mg were applied on roughened PMMA plates and the transmission measurements are carried out using a spectrophotometer equipped with integrating sphere. Eighteen oily ingredients were studied. Each one of them was incorporated in the amount of 20%. It is the lanolin which appears most effective SPF booster. Then oils come blackcurrant, argan, sweet almond, sesame, groundnut, carthame and palmotene

Anti-inflammatory effect of UV-filters tested at the maximum authorized concentration.

<p>Anti-inflammatory effect of UV-filters tested at the maximum authorized concentration.</p

Dose Response Relationship for UV-filters limited to 8% (w/w).

<p>Dose Response Relationship for UV-filters limited to 8% (w/w).</p

Dose Response Relationship for Diethylaminohydroxybenzoyl hexyl benzoate.

<p>Dose Response Relationship for Diethylaminohydroxybenzoyl hexyl benzoate.</p

Anti-inflammatory effect of references.

<p>Anti-inflammatory effect of references.</p

Sunscreen products tested.

<p>Sunscreen products tested.</p

Molecular structures.

<p>Molecular structures.</p