Attachment of a Frog Skin-Derived Peptide to Functionalized Cerium Oxide Nanoparticles

Peptide Brevinin-2R (B2R) has derived from frog skin secretions and possesses cytotoxic effects on cancer cells. Beside, cerium oxide nanoparticle (CNP) has antioxidant properties and could be used in anticancer studies. The purpose of this study is to investigate antioxidant and cytotoxicity of cerium oxide nanoparticle conjugated with B2R. First, cerium oxide nanoparticles were amine functionalized and peptide attached to it through establishment of peptide bond. Then, (1,1-diphenyl-2-picrylhydrazyl) DPPH and 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical scavenging activities of CNP-B2R were determined. MTT assay were used in order to compare cytotoxicity of CNP- B2R on two different cell lines. HFLF-pI5 cell and A549 cell lines were selected as representative of normal and cancer cells, respectively. Also, the cytotoxic effects of CNP, B2R and CNP-B2R were investigated on A549 cell line. Results of antioxidant evaluations showed that the antioxidant activity of CNP-Peptide increased at higher concentration of CNP-B2R with IC 50 of 0.2 and 0.54 (mg/mL) for DPPH and ABTS assays, respectively. The results of cytotoxicity effects showed that CNP-B2R was more potent in killing tumor cell line in comparison with normal cell line. Cytotoxicity of CNP, B2R and CNP-B2R demonstrated that CNP-B2R and B2R had the lower cell viability effects compared to CNP. Our findings showed cytotoxicity of CNP-B2R against cancer cell lines in comparison with normal cells indicating the potential anticancer properties of CNP-B2R.