[The relationship between histone H3Ser10 phosphorylation and DNA damage in periphery blood lymphocytes of polycyclic aromatic hydrocarbons exposed workers]

Objective: To investigate the effect of polycyclic aromatic hydrocarbons (PAHs) exposure on the level of histone H3Ser10 phosphorylation (p-H3S10) and DNA damage degree in peripheral blood lymphocyte (PBLCs). Method: 75 coke oven workers from Benxi steel plant in Liaoning Province of China (PAHs-exposed group) and local 50 hot rolling workers (control group) were recruited in this study with age, working years, labor intensity and high temperature for matching factors using cluster sampling method in 2014. HPLC-fluorescence was performed to determine the level of urinary 1-hydroxypyrene (1-OHP), DNA damage and specific histone modification were measured in PBLCs of the subjects through comet assay and ELISA assay, respectively. Linear regression model analysis was used to analyze the differences among PAHs exposure, DNA damage and p-H3S10 level in two groups. The Mediation analysis was used to analyze the regulated relationships between urinary 1-OHP, DNA damage and histone modification through the bootstrap method. Results: Age of the control and the exposed group were (45.32±8.32) and (43.87±5.67) years old (P=0.284). The concentration of urinary 1-OHP, OTM value, Tail DNA% and p-H3S10 level in exposure group were higher than that in control group, while the M (P(5)-P(95)) of p-H3S10 levels in control and exposed group were 2.21 (0.68-4.71), 4.54 (1.85-23.91) (P<0.001). The degree p-H3S10 level was increased after the subgroups which were (2.59±1.19)%, (3.24±2.81)%, (5.55±3.25)%, (8.77±7.84)%, respectively, divided by quantitated 1-OHP concentration as P(0)-P(25), P(26)-P(50), P(51)-P(75) and P(76)-P(100) (P<0.001). We also found the correlations between urinary 1-OHP and p-H3S10 level or OTM value or Tail DNA%, β (95%CI) were 0.264 (0.167-0.360), 0.500 (0.299-0.702), and 0.510 (0.384-0.671), respectively (P<0.001). Similar result was also observed between p-H3S10 level and OTM value or Tail DNA%, β (95%CI) were 0.149 (0.073-0.226) and 0.220 (0.132-0.308) (P<0.001). Moreover, the mediation effect value of DNA damage on PAHs induced p-H3S10 alteration was 0.054(P=0.040). Conclusion: The results suggested that PAHs exposure could induce DNA damage and an increase in histone H3Ser10 phosphorylation in PBLCs. Particularly, the alteration of H3S10 phosphorylation may play an important role in regulating cell DNA damage repair.