Fig. 1
Analysis of the mechanism of cytotoxicity induced by excessive Zn2+. (A) MC3T3-E1 cells were incubated with cell medium containing different concentrations of Zn2+ for 24 h, and cell counting kit-8 (CCK-8) assay was used to detect cell viability. (B) Top: apoptotic cells were detected using a Terminal dUTP nick-end labeling (TUNEL) assay. Bottom: intracellular Zn2+ concentrations in MC3T3-E1 were detected using a Zn2+ fluorescence probe (FluoZin-3, AM). (C) The quantification analysis of positive TUNEL cells. (D) The fluorescence quantification analysis of intracellular Zn2+ concentrations. (E) RNA transcriptome sequencing analysis of MC3T3-E1 cells treated with excessive Zn2+ (180 µM) or control (n = 3). Heatmap of top-100 highly variable genes. (F) GO enrichment analysis results. (G–H) The expression Zip1-Zip14 mRNA and genes associated with osteogenesis (Runx2, Alpl, Osterix mRNA) in control cells or MC3T3-E1 cells treated with excessive Zn2+ were detected using RT-qPCR (n = 3). Bars represent mean ± S.D. *p < 0.05; **p < 0.01