Influence of phloretin and 6-ketocholestanol on the permeation of progesterone through porcine skin

In this study the effect of phloretin (PH) and 6-ketocholestanol (KC) on th e permeation of progesterone through porcine skin has been examined. Both P H and KC were incorporated into unilamellar L-cl-phosphatidylcholine (PC) l iposomes at different concentrations (7.5, 15, 30 and 60 mol%). In diffusio n experiments with porcine skin, both substances, to a different degree, en hanced the steady state flux of progesterone. Tt was increased up to 2.4-fo ld using 15 mol% KC, and 1.4-fold using 30 mol% PH.. The results indicate a n interaction of these two compounds with the lipid components of the strat um corneum. In order to visualise the interaction, differential scanning ca lorimetry (DSC) measurements were performed on porcine skin, which had been impregnated with KC and PH. Both showed a lowering (similar to 5-6 degrees C) in the lipid phase transition temperature that occurs around 75 degreesC in porcine skin. (C) 2001 Elsevier Science B.V. All rights reserved.