Preparation, Stability and In Vitro Antineoplastic Function of Lecithin–Chitosan–Polyethylene Glycol Nanoparticles Loaded with Bioactive Peptides Derived from Phycocyanin

Phycocyanin (PC) is a type of alga-derived protein which exerts the role of light harvesting in <i>Spirulina</i> and <i>Cyanophyta</i> cells. Studies have widely proved that phycocyanin exhibits antineoplastic functions, while investigations on its bioactive peptides remain poorly documented. In previous work, three phycocyanin-derived peptides (PCPs: PCP1-3), which exerted anticancer effects in non-small cell lung cancer (NSCLC) cells, were successfully identified. In consideration of the in vitro instability of bioactive peptides, this study firstly investigated the stabilization and function of phycocyanin-derived peptides loaded by nanoparticles (NPs). Herein, Lipid-core NPs (PCPs@LEC-CS-PEG, diameter less than 100 nm) were prepared by interfacial deposition of a polymer using lecithin (LEC, liposome core shell), chitosan (CS, coating material) and polyethylene glycol (PEG, stabilizer). The results indicate that the embedding of LEC liposomes could significantly increase the stability of PCPs through promoting their resistance to high temperature (68.256 ± 3.26%), pH (60.17 ± 3.67%) and protease. Moreover, the modification of NPs by PEG and CS could enhance the protective effects on PCPs. Furthermore, in vitro phenotypic experiments confirmed that the inclusion of PCPs@PEG-CS-LEC NPs also significantly increased the inhibitory activities of PCPs against multiple NSCLC cells including A549, H1299 and LTEP-a2 cells, compared with non-embedded PCPs. The results of this work could lay a theoretical foundation for the further development and utilization of peptides derived from phycocyanin, and also for the investigation of the antineoplastic effects of bioactive peptides.