Effect of nano-SiO_2 on the survival and PARP-1 expression in 16HBE cells / 中国职业医学

ABSTRACT

OBJECTIVE: To explore the effects of nano-silicon dioxide( SiO_2) on the survival and poly( ADP-ribose)polymerase-1( PARP-1) expression in human bronchial epithelial cells( 16 HBE cells). METHODS: i) The 16 HBE cells were treated with nano-SiO_2 at concentrations ranging from 0 to 100 mg/L for 24. 0 hours,and CCK-8 assay was used to examine cell viability. ii) The 16 HBE cells were divided into 6 groups solvent control group( equal volume solvent treatment),micro-SiO_2 control group( treated with 20 mg/L micro-SiO_2),5,10,and 20 mg/L nano-SiO_2 groups( treated with the corresponding final dose of nano-SiO_2),and curcumin group. The curcumin group was given pretreatment with curcumin at a final concentration of 10 μmol/L for 2. 0 hours followed by treatment with a final concentration of 20 mg/L of nano-SiO_2. Cells in each group were harvested at time points of 4. 0,12. 0 and 24. 0 hours after treatment. The relative expression of PARP-1 mRNA and protein in 16 HBE cells was detected by quantitative real-time polymerase chain reaction and Western blotting respectively. RESULTS: i) The survival of 16 HBE cells decreased with increasing nano-SiO_2 treatment dose,showing a dose-effect relationship( P < 0. 01). ii) The expression of PARP-1 mRNA and protein in 16 HBE cells were dose-dependently decreased after nano-SiO_2 stimulation at the 12. 0 and 24. 0 hours time points( P < 0. 01). The expression of PARP-1 mRNA and protein in 5,10,and 20 mg/L nano-SiO_2 groups decreased at the above mentioned time points( P < 0. 05),compared with the solvent control group at the same time points. The expression of PARP-1 mRNA and protein in 20 mg/L nano-SiO_2 group was lower than that in the micro-SiO_2 control group at the same 12. 0 and 24. 0 hours time point( P < 0. 05). The above two indexes of cells were higher in curcumin group than that of 20 mg/L nano-SiO_2 group at the 12. 0 hours time point( P < 0. 05). CONCLUSION: Nano-SiO_2 stimulation can lead to decrease survival of 16 HBE cells in a dose-dependent manner and down-regulation of PARP-1 expression may be one of the mechanisms of proliferation and inhibition of 16 HBE cells induced by nano-SiO_2. Curcumin has certain protective effect on nano-SiO_2-induced 16 HBE cell injury.