Neuroprotective action of undecylenic acid (UDA) encapsulated into PCL nanocarriers

The main goal of the presented research was to investigate the biocompatibility of polycaprolactone (PCL)-based nanoparticles and to evaluate the neuroprotective action of the encapsulated, water-insoluble neuroprotective substance - undecylenic acid (UDA). The neuroprotectant-loaded nanoparticles (NPs) were prepared from polymer containing toluene based nanoemulsions formed by the phase inversion composition (PIC) technique followed by solvent evaporation. Two types of PCL-based UDA-loaded nanoparticles were synthesized: PCL and PCL-PEG (using poly(ethylene glycol)-block-poly(epsilon-caprolactone) methyl ether). The average size of PCL/UDA NCs was around 120 nm and for PCL-PEG/UDA around 150 nm. The concentration of both types of NCs was similar: 2 x 10(10) particles ml(-1) and the zeta potential of UDA-loaded PCL and PCL-PEG NCs -24 mV and -21 mV respectively. Biocompatibility of synthesized nanocarriers was evaluated in the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). The PCL and PCL-PEG nanocarriers at concentration 0.5 x 10(10) particles ml(-1) did not show deleterious effects on human neuroblastoma cells line. The neuroprotection studies revealed that UDA loaded in PCL or PCL-PEG nanocarriers retained its neuroprotective potential against Staurosporine-evoked SH-SY5Y cell damage.