Biocompatibility and neuroprotective potential of encapsulated S-Allyl-L-Cysteine into PCL-based nanocarrier

Background and Objectives: Recently S-Allyl-L-Cysteine (SAC) (an organic compound that is a natural constituent of garlic, is a derivative of the amino acid cysteine) has been introduced as an agent of suppression of μ- and m-calpain activities and followed by that bright promising neuroprotective compound. The main objective of this research was to evaluate the biocompatibility and neuroprotective potential of the encapsulated S-Allyl-L-Cysteine (SAC) into polycaprolactone (PCL)-based nanocarriers (NCs).

Methods: The copolymer-based SAC-loaded nanocarriers were prepared from coprecipitation method at constant temperature followed by evaporation of the organic solvent. To the best of our knowledge, it is the first time to investigate the biocompatibility and neuroprotective potential of SAC loaded into PEG-b-PCL (poly(ethylene glycol)-block-poly(ε−caprolactone) methyl ether).

Results: The average size of the PEG-b- PCL/empty NCs was 108 nm and for PEG-b-PCL/SAC was 124 nm. The Drug Loading efficiency was 68%. The concentration of PCL-based NCs was 2 x 10 10 particles/ml and the zeta potential of PEG-b- PCL/empty and PEG-b-PCL/SAC NCs was -17 mV and - 23 mV respectively. Biocompatibility and Neuroprotective potential of NCs were evaluated in the SHSY5Y human neuroblastoma cell line using cell viability and toxicity assays.

Conclusion: The concentration of PEG-b-PCL NCs below 1 x 10 10 particles/ml can be considered as a safe concentration for the cell line. Also, the SAC encapsulated into PEG-b-PCL NCs has the same neuroprotective effect as free SAC at lower concentration, and therefore, has a significant neuroprotective potential against Z-VAD-fmk and St-evoked SH-SY5Y cell damage.