The potential for colloidal carriers to increase drug bioavailability has spurred a renewed interest in their uptake mechanisms and movement within cells. Solid lipid nanoparticles (SLN) were used as a carrier for a promising chemopreventive drug, resveratrol (RSV). The effects of SLN, empty or loaded with RSV (SLN-RSV), on the internalization, growth, morphology, metabolic activity and genetic material of keratinocytes were compared to those of RSV in solution. Fluorescence images clearly showed that SLN with a size below 180 nm move promptly through the cell membrane, distribute throughout the cytosol, move successively among different cellular levels and localize in the perinuclear region without inducing cytotoxicity. RSV solubility, stability and intracellular delivery were all increased by loading into SLN. The release profile of RSV showed a biphasic pattern, reflecting its distribution in SLN. RSV in solution was slightly cytotoxic. That was prevented by loading it into solid lipid nanoparticles, which preserved cell morphology. The cytostatic effect of SLN-RSV was much more expressed than that of RSV in solution. Delivery of RSV by SLN contributes to effectiveness of RSV on decreasing cell proliferation, with potential benefits for prevention of skin cancer.
Copyright 2009 Elsevier B.V. All rights reserved.