The role of chitosan as coating material for nanostructured lipid carriers for skin delivery of fucoxanthin.

Fucoxanthin (FUCO) is a marine carotenoid characterized by antiproliferative properties against hyperproliferative cells. The aim of this work was to design and develop nanostructured lipidic carriers (NLCs) based on bacuri butter and tucumã oil and loaded with FUCO, intended for skin application to prevent skin hyperproliferative diseases and in particular psoriasis. The presence of FUCO should control the hyperproliferation of skin diseased cells and the lipids forming the NLC core, rich in antioxidants and characterized by wound healing properties, should favor the restoring of skin integrity. NLCs were coated with chitosan (CS) to improve their biopharmaceutical properties (bio/mucoadhesion and wound healing) and to combine the advantages of lipidic nanoparticles with the biological properties of CS. Chitosan coated and non-coated NLC were prepared by means of high shear homogenization and characterized for chemico-physical and biopharmaceutical properties (in vitro biocompatibility and cell uptake towards normal dermal human fibroblasts). Moreover, the pharmacological activity of FUCO loaded in NLCs was assessed in psoriatic-like cellular model. NLCs were characterized by dimensions ranging from about 250 to 400 nm. Moreover, the CS coating and FUCO loading determined an increase of size. Moreover, TEM and zeta potential analysis confirmed the presence of CS coating on nanoparticle surface, thus conferring to nanoparticle good bioadhesion properties. NLCs uptake in fibroblasts was observed and NLC-FUCO-CS caused a reduction of cell viability with a less marked effect in fibroblasts rather than in psoriatic cells, highlighting the capability of this system to control skin hyperproliferation and inflammation. The loading of NLC-FUCO-CS in pullulan film should render NLCs application easy, without impair prompt interaction of the drug with the skin. Considering the overall results skin application of CS coated NLCs loaded with FUCO seems a promising approach to control skin hyperproliferation and to preserve skin integrity in psoriatic skin.