Different Cellular Effects of Platinum Nanoparticles on RAW 264.7 Cells.

The cellular effects of platinum nanoparticle (PtNP) and platinum nanocolloid (PtNC) were investigated on murine leukemia Raw 264.7 cells. PtNP induced strong cytotoxic effects on Raw 264.7 cells while PtNC showed only mild cytotoxicity. Dramatic reduction in cell growth and morphological changes were observed for cells treated with PtNPs while PtNC did not show these effects. Both PtNPs and PtNC suppressed nitric oxide production, but PtNPs were superior to PtNC. PtNP strongly suppressed the expression of iNOS, COX-2 proteins and the phosphorylation of AKT on LPS-stimulated Raw 264.7 cells while PtNC showed only weak effects on these proteins. Our data showed that the preparation method of platinum nanoparticles may cause different cellular effects on cell growth and signaling.