Mediation Effect Of Telomere Length Between Polycyclic Aromatic Hydrocarbons Exposure And Abnormal Glucose Level In Coke-oven Plant Workers

Objective:To investigated the dose-response relationship between exposure to polycyclic aromatic hydrocarbons(PAHs)and fasting blood glucose levels and telomere length among coke-oven plant workers.To investigate the correlation between telomere length,PAHs exposure and fasting blood glucose level,in order to explore the role of telomere length in this study.To explore the risk of abnormal glucose from the perspectives of environmental factors and genetic factors,in order to provide a theoretical basis for the prevention of diabetes and the confirmation of early detection indexes in coking workers.Methods:692 workers were enrolled from a cross-sectional survey of a coking plant in Shanxi Province in 2017.The basic health information of workers was collected by an interviewer-administered questionnaire.Morning urine and blood samples were collected,and we used high performance liquid chromatography mass spectrometry(HPLC-MS)to detect 11 urine biomarkers of PAHs exposure,including 1-hydroxynaphthalene(1-NAP),2-hydroxynaphthalene(2-NAP),2-hydroxyfluorene(2-FLU),3-hydroxyfluorene(3-FLU),1-hydroxyphenanthrene(1-PHE),2-hydroxyphenanthrene(2-PHE),9-hydroxyphenanthrene(9-PHE),1-hydroxypyrene(1-PYR),3-hydroxychrysene(3-CHR),6-hydroxychrysene(6-CHR)and 9-hydroxybenzpyrene(9-BAP)levels.the Real-time quantitative polymerase chain reaction(RT-q PCR)method was used to measured peripheral blood telomere length.A modified Poisson regression models was used to assessthe dose-response relationship between urinary PAHs metabolite levels and abnormal glucose,and the dose-response relationship between urinary PAHs metabolites and peripheral blood telomere length was evaluated using a multiple logistic regression model,respectively.Mediating effect analysis was used to investigate the role of telomere length in urinary PAHs metabolites and abnormal fasting blood glucose levels.Results:1.The participants was divided into normal(? 5.6 mmol/L)group and abnormal(>5.6 mmol/L)group by the fasting blood glucose levels.In the present study,the mean age of participants was 40 years old,and 12.57%(87/692)had abnormal glucose.Abnormal glucose was observed among older adults,male,current smokers and drinkers and those who with higher BMI(P < 0.05).The median concentrations of urinary 1-PYR was 0.09ng/ml in total,the levels of 1-PYR were higher among the abnormal glucose group(P <0.05).And the median level of TL was 0.39(T/S)in total,there was no significant statistical difference in telomere length and other urinary PAHs metabolites between the normal group and the abnormal group(P> 0.05).2.Modified Poisson regression suggested increasing levels of urinary 1-PYR was positively associated with abnormal glucose in a dose-dependent manner(Ptrend=0.007),after adjusting for age,sex,smoking,drinking,heating mode,BMI,physical activities,eating habits(taste,vegetables and fruit)and other PAHs metabolites.Urinary 1-PYR in the 3rd tertile was associated with an 8%(95% CI: 1.01-1.16)higher prevalence ratio of abnormal glucose.3.Multiple logistic regression suggested increasing levels of urinary 1-PYR was negatively associated with telomere length in a dose-dependent manner(Ptrend=0.045),after adjusting for age,sex,smoking,drinking,heating mode,BMI,physical activities,eating habits(taste,vegetables and fruit)and other PAHs metabolites.The ORs(95% CI)were0.47(0.28-0.79)for 2nd tertile and 0.41(0.23-0.76)for 3rd tertile,compared with 1st tertile,respectively.4.The association of 1-PYR and abnormal glucose was further quantified acrosstelomere length tertiles.After adjusting for age,sex,smoking,drinking,heating mode,BMI,physical activities,eating habits(taste,vegetables and fruit)and other PAHs metabolites,modified Poisson regression suggested increasing levels of urinary 1-PYR was positively associated with abnormal glucose in a dose-dependent manner(Ptrend=0.006),and urinary 1-PYR in the 3rd tertile was associated with a 16%(95% CI:1.02-1.31)higher prevalence ratio of abnormal glucose among participants with median telomere length levels.5.There was a marginal mediation effect of telomere length in the association between 1-PYR and abnormal glucose among participants with median telomere length levels(P = 0.098).The telomere length could explain 11.7%(2.2%-43.3%)of effect of abnormal glucose related to PAHs exposure among participants with median telomere length levels.Conclusion:1.PAHs exposure was positively associated with abnormal glucose in coke-oven plant workers.And there was a dose-response relationship between PAHs exposure and abnormal glucose.2.PAHs exposure was negatively associated with telomere length in coke-oven plant workers.And there was a significant dose-response relationship between PAHs exposure and telomere length.3.Telomere length was associated with abnormal fasting glucose levels due to PAHs exposure.And the effect of PAHs-related abnormal glucose may be mediated by telomere length.