Abstract: BACKGROUND ＆ AIM: To investigate DNA damage of human umbilical vein endothelial cells after treated with formaldehyde, H2O2, formaldehyde and H2O2. MATERIAL AND METHODS: ①Comet assay was employed to assess DNA damage of human umbilical vein endothelial cells treated with either various concentrations (0,5,10,25,50, 100 μmol/L) of formaldehyde, H2O2, formaldehyde and H2O2 for 20 min or 25 μmol/L formaldehyde, H2O2, formaldehyde and H2O2 for different time(0,10,20,30 min) to quantify the DNA damage. ②K-SDS was employed to evaluate DNA-Protein cross-link(DPC) of endothelial cells treated with either various concentrations of formaldehyde, formaldehyde and H2O2(0, 10, 50, 100, 500, 1 000, 2 000 μmol/L) for 1.5 h or 50 μmol/L and 100 mol/L formaldehyde, formaldehyde and H2O2 for different time(0,0.5,1,1.5,2,4 h) to quantify the DPC. RESULTS: DNA breakage caused by 5,10,25 μmol/L formaldehyde was significantly different from control, and might be increased by H2O2. Tail moment was time-dependent when treated with 25 μmol/L formaldehyde. The formation of DPC increased(P<0.05)after treated with various concentrations of formaldehyde for 1.5 h. CONCLUSION: ①Formaldehyde can cause DNA breakage(<25 μmol/L) and DPC(>500 μmol/L), both were concentration and time-dependent.②H2O2 can cause DNA breakage, which was concentration and time-dependent. 　　

Key words: human umbilical vein endothelial cells, comet assay, K-SDS, DNA-damage