Lipopolysaccharide Stimulation Induces DNA Double-strand Breaks in Dental Pulp Cells.

doi:10.13701/j.cnki.kqyxyj.2017.03.001

Abstract

Abstract: Objective: To investigate whether low dose of lipopolysaccharide (LPS) induces DNA damage in dental pulp cells, and to provide an experimental model for studying the DNA double-strand breaks and DNA repair. Methods: Ten μg/L LPS was added to dental pulp cells constantly once, three times, and six times, respectively. Cell proliferation was detected by MTT assay. Cell apoptosis was detected by TUNEL assay. The mRNA and protein expression levels of γ-H2A.X were investigated by q-PCR and Western blot. The expressions of γ-H2A. X in vivo or vitro were detected by immunofluorescence and immunohistochemistry. Results: Compared with the control group, the repeated stimulation of 10μg/L LPS had no significantinfluence on cell proliferation or on cell apoptosis. After repeated stimulation of 10μg/L LPS for six times,immunofluorescence revealed the positive expression of γ-H2A.X in cell nucleus. Moreover, compared with control groups, the mRNA and protein expression levels of γ-H2A.X increased significantly (P<0.05). Immunohistochemistry showed γ-H2A.X expression level increased remarkably after being induced by LPS for 4, 6 and 8days, respectively (P<0.05). Conclusion: The repeated stimulation of low dose of LPS may induce the occurrence of DNA double-strand breaks in dental pulp cells.

Key words: Lipopolysaccharide , Dental pulp cell, DNA double-strand breaks , γ-H2A.X

CLC Number:

R780.1

HUANG Ye-quan, MENG Liu-yan, QIAO Wei-wei, BIAN Zhuan. Lipopolysaccharide Stimulation Induces DNA Double-strand Breaks in Dental Pulp Cells.[J]. Journal of Oral Science Research, 2017, 33(3): 235-239.

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