In Vivo Biological Evaluation of Polyurethane Nanostructures with Ursolic and Oleanolic Acids on Chemically-induced Skin Carcinogenesis

Abstract

Background/Aim: Oleanolic and ursolic acids (OA and UA) are two pentacyclic triterpenes, ubiquitously spread in plants, previously known for their chemopreventive capacity on different types of cancer. The major pharmacological disadvantage of these phytocompounds is their poor water solubility, which often limits their applicability. Materials and Methods: Using the interfacial polycondensation combined with spontaneous emulsification technique, polyurethane nanostructures (PU) were synthetized in order to improve this problem. In order to test the in vivo chemopreventive potential of the two pure compounds, as well as the encapsulated compounds in PU used as drug carriers, a chemically-induced skin carcinogenesis model was constructed. Results: UA and OA have a moderate chemopreventive activity against tumors induced by 7,12-dimethylbenzantracene (DMBA) and 12-O-tetradecanoilphorbol-13-acetate (TPA) application. Incorporation of active agents in PU did not lead to increased chemopreventive effect. Conclusion: PU is not a suitable formulation of UA and OA.