Hélen Cássia Rosseto, Lucas de Alcântara Sica de Toledo, Lizziane Maria Belloto de Francisco, Elisabetta Esposito, Yunsook Lim, Giuseppe Valacchi, Rita Cortesi, Marcos Luciano Bruschi (2017). Nanostructured lipid systems modified with waste material of propolis for wound healing: Design, in vitro and in vivo evaluation. Colloids and Surfaces B: Biointerfaces, 158(441-452).
a. Postgraduate Program in Pharmaceutical Sciences, Laboratory of Research and Development of Drug Delivery Systems, Department of Pharmacy, State University of Maringa, Maringa, Parana, Brazil
b. Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
c. Department of Food and Nutrition, Kyung Hee University, Seoul, South Korea
d. Animal Science Department, Plants for Human Health Institute, NC Research Campus, NC State University, Kannapolis, USA
Propolis, a natural compound that can accelerate the wound healing process, is mainly used as ethanolic extract. The extractive solution may also be obtained from the propolis by-product (BP), transforming this waste material into a pharmaceutical active ingredient. Even if propolis does not show toxicity, when used as an extract over harmed skin or mucosa, the present ethanol content may be harmful to the tissue recovering, besides hindering the drug release. This study describes the development of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) as topical propolis delivery systems and the investigation of their in vitro and in vivo activities. The extracts were evaluated to guarantee their quality, and the lipid dispersions were characterized with respect to morphology (cryo-TEM), size and diffractometry (X-ray) properties. The occlusive capacity of formulations was also evaluated by an in vitro technique, which determines the occlusion factor. The drug entrapment efficiency (EE), as well as the in vitro drug release profile from the nanoparticulate systems was investigated as well. The size analysis performed through 90 days was favorable to a topical administration and the polydispersity index, though not ideal in all cases due to the high content of resins and gums from the extracts, were relatively stable for the SLN. The propolis extract contributes to the occlusive potential of the formulations. The human immortalized keratinocytes presented good cell viability when tested with both extracts (propolis and BP) freely or entrapped in the systems. SLN modified with propolis material provided an acceleration of the in vivo wound healing process.