Lipid Nanoparticles Loading Steroidal Alkaloids of Tomatoes Affect Neuroblastoma Cell Viability in an In Vitro Model

Tomato by-products represent a good source of phytochemical compounds with health properties, such as the steroidal glycoalkaloid ?-tomatine (?-TM) and its aglycone tomatidine (TD). Both molecules have numerous beneficial properties, such as potential anticancer activity. Unfortunately, their therapeutic application is limited due to stability and bioavailability issues. Therefore, a valid strategy seems to be their encapsulation into Solid Lipid Nanoparticles (SLN). The nanoformulations containing ?-TM (?-TM-SLN) and TD (TD-SLN) were prepared by solventdiffusion technique and subsequently characterized in terms of technological parameters (particle size, polydispersity index, zeta potential, microscopy, and calorimetric studies). To assess the effect of ?-TM and TD on the percentage of cellular viability in Olfactory Ensheathing Cells (OECs), a peculiar glial cell type of the olfactory system used as normal cells, and in SH-SY5Y, a neuroblastoma cancer cell line, an MTT test was performed. In addition, the effects of empty, ?-TMSLN, and TD-SLN were tested. Our results show that the treatment of OECs with blank-SLN, free ?-TM (0.25 µg/mL), and TD (0.50 µg/mL) did not induce any significant change in the percentage of cell viability when compared with the control. In contrast, in SH-SY5Y-treated cells, a significant decrease in the percentage of cell viability when compared with the control was found. In particular, the effect appeared more evident when SH-SY5Y cells were exposed to ?-TM-SLN and TD-SLN. No significant effect in blank-SLN-treated SH-SY5T cells was observed. Therefore, SLN is a promising approach for the delivery of ?-TM and TD.