Sodium perbarate and benzalkonium chloride induce DNA damage in Chang conjunctival epithelial cells.
Content and objective: To investigate and compare the toxic effects of benzalkonium chloride (BAC) and new type oxidative preservative sodium perborate (NaBO3) on DNA damage, reactive oxygen species (ROS), and cell survival in immortalized human Chang conjunctival cells.


METHODS
Cells were exposed to BAC and NaBO3in concentrations of 0.00001-0.001% for 30 min. Cell viability was measured by the MTT test. Alkaline comet assay was used to detect DNA damage. Mitochondrial membrane potential (MMP), cell apoptosis, and ROS production were detected by flow cytometry analysis.


RESULTS
Significant changes in the relative cell survival rate in cells were observed after exposure to 0.0005-0.001% BAC for 30 min (p < 0.001). DNA damage and intracellular ROS were observed in a dose-dependent manner with BAC exposure (p < 0.001). However, 0.001% BAC induced less ROS than 0.0005% BAC. A decrease in MMP was also recorded. NaBO3did not induce the decrease in cell survival and MMP in low concentration but could induce DNA damage and ROS generation in a 0.001% concentration (p < 0.001).


CONCLUSIONS
BAC can induce DNA damage in human conjunctival epithelial cells; this effect may be related to oxidative stress. Although NaBO3did not induce a significant decrease in cell survival and MMP, DNA damage and ROS generation were still detected in high concentration. New type oxidative preservative has less toxicity than the old type, but it still has the tendency of producing genotoxic changes in an in vitro test system.
a Department of Ophthalmology , The second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , China and.
Huina
H
Zhang
a Department of Ophthalmology , The second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , China and.
Han
H
Wu
b Department of Toxicology , Hangzhou Normal University School of Public Health , Hangzhou , China.
Jun
J
Yang
a Department of Ophthalmology , The second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , China and.
Juan
J
Ye
D017209:Apoptosis / Q000187:drug effects; D001548:Benzalkonium Compounds / Q000633:toxicity*; D001881:Borates / Q000633:toxicity*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D003228:Conjunctiva / Q000166:cytology*; D004249:DNA Damage; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D011310:Preservatives, Pharmaceutical / Q000633:toxicity*; D017382:Reactive Oxygen Species / Q000378:metabolism
D001548:Benzalkonium Compounds; D001881:Borates; D011310:Preservatives, Pharmaceutical; D017382:Reactive Oxygen Species; C027707:sodium perborate
Benzalkonium chloride; Chang conjunctival cells; DNA damage; preservative; reactive oxygen species; sodium perbarate