title: Percutaneous penetration and skin metabolism of ethylsalicylate-containing agent, TU-2100: in-vitro and in-vivo evaluation in guinea pigs.
abstract: The aim of this study was to investigate the percutaneous penetration and dermal metabolism of a new potential anti-acne prodrug--TU-2100 [bis(o-carboxyphenyl ethyl ester)nonanedioate] in guinea pigs. The fluxes of this agent through excised skin after applications of TU-2100 gels at 3 and 10% concentrations were similar. However, after 24 h from the time of drug application, the total amounts of permeated TU-2100 into the skin compartment and through the skin into the receiver were 271.7 (+/-30.7 S.E.) microg/cm(2) from the 3% gel and 779.4.0 (+/-98.5 S.E.) microg/cm(2) from the 10% gel, demonstrating a relatively high skin accumulation. Higher degradation of TU-2100 to ethylsalicylate occurred after application of drug at 10% concentration than after the application of 3% gel. In contrast, the fraction of permeated drug metabolized was twofold higher after the 3% gel application than after the 10% gel (F(m)=20 vs. 10.5 mole %). Since F(m) is reversibly related to the total permeating drug, the obtained values actually reflect the significant difference in TU-2100 permeation from the 3% (271.7 microg) and the 10% (779.4 microg) gels. An in vivo--in vitro comparison revealed similar drug accumulations in the skin after application of both 3 and 10% gels, however, skin metabolism was found to be significantly higher in vivo than in vitro.
authors.affiliation: Ben Gurion University of the Negev, The Institutes for Applied Research, 84105, Beer Sheva, Israel. asintov@bgumail.bgu.ac.il
authors.forename: Amnon C
authors.initials: AC
authors.lastname: Sintov
authors.forename: Clara
authors.initials: C
authors.lastname: Behar-Canetti
authors.forename: Yeshayahu
authors.initials: Y
authors.lastname: Friedman
authors.forename: Dov
authors.initials: D
authors.lastname: Tamarkin
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D003879:Dermatologic Agents / Q000737:chemistry / Q000493:pharmacokinetics*; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005782:Gels; D006168:Guinea Pigs; D007509:Irritants / Q000737:chemistry / Q000493:pharmacokinetics; D008297:Male; D011355:Prodrugs / Q000737:chemistry / Q000493:pharmacokinetics; D012459:Salicylates / Q000737:chemistry / Q000493:pharmacokinetics*; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D012869:Skin Absorption / Q000187:drug effects / Q000502:physiology
chemical_list: D003879:Dermatologic Agents; D005782:Gels; D007509:Irritants; D011355:Prodrugs; D012459:Salicylates; C041835:ethyl salicylate