cytotoxic effects of combined walnut shell-extracted copper oxide: nanoparticles and hydroalcoholic extracts of aloe vera against human leukemic cell line

Background: anticancer effects of aloe vera and copper oxide nanoparticles (cuo nps) have been separately determined. hence, we investigated whether combining the hydroalcoholic extract of aloe vera and green cuo nps produced by eco-friendly and walnut shells could provide synergistic cytotoxicity against k562 cell lines. methods: the k562 cells and pbmcs (1 × 105 cells/100 μl/well) were treated with serial dilution of aloe vera extract (0, 20, 40, 60, 80, 160 and 320 mg/ ml) and green cuo nps (0, 50, 100, 200 and 400 μm). after incubation for 24h, the viability of cells was determined by mtt assay. cells were exposed to a mixture of aloe vera extract and green cuo nps at the half-maximal inhibitory concentration (ic50) to assess the inhibitory effects. results: the extract of aloe vera and green cuo nps had cytotoxic effects against k562 (cell-line in a dose-dependent manner). unlike aloe vera, the marginal safety of green cuo nps was low. there were no significant dissimilarities in the ic50 value of the green cuo nps against k562 cells compared to the ic50 value of the green cuo nps against pbmcs (175 ± 9 μm vs. 186.89 ± 8.88 μm). combined treatment with minimal cytotoxic doses provided synergistic benefits and caused more cytotoxicity in k562 cells toward their separated treatment. meanwhile, this combined concentration enhanced the cell-survival, not the cytotoxicity in pbmc treated cells. conclusions: the combinative concentration of aloe vera and green cuo may be considered alternative medicine later.