title: Evaluation of the mechanism of nucleoplasmic bridge formation due to premature telomere shortening in agricultural workers exposed to mixed pesticides: indication for further studies.
abstract: Agricultural workers are often exposed to high levels of pesticides over prolonged periods of time. We attempted to determine whether exposure to multiple pesticides shortens relative telomere length (RTL) and causes nucleoplasmic bridge (NPB) formation via the mechanism of telomere-end fusion in the lymphocytes of agricultural workers. For measuring RTL, we used quantitative fluorescent in situ hybridization, while NPB frequency was measured as part of the cytome assay. Multivariate analysis of variances taking into account confounding factors (age, gender, years of exposure, smoking, and alcohol intake) did not show a decrease, but rather an increase of RTL in agricultural workers compared to control individuals. In the exposed population, NPB frequency was significantly higher compared to controls (6 times, p<0.05). Multiple regression between NPB, RTL, and confounding factors was not significant. Using Spearman correlation, we did not find proof for our initial hypothesis. Our hypothesis that telomere shortening is a mechanism of NPB origin was not proven, indicating that telomere-end fusion is not a mechanism of NPB formation under our experimental conditions for agricultural workers.
authors: Division for Mutagenesis, Institute for Medical Research and Occupational Health, Ksaverska 2, 10000 Zagreb, Croatia.
authors: Davor
authors: D
authors: Zeljezic
authors: Economic High School Velika Gorica, Ulica Kralja Stjepana Tomaševića 21, 10410 Velika Gorica, Croatia.
authors: Marija
authors: M
authors: Bjelis
authors: Division for Mutagenesis, Institute for Medical Research and Occupational Health, Ksaverska 2, 10000 Zagreb, Croatia. Electronic address: mmladinic@imi.hr.
authors: Marin
authors: M
authors: Mladinic
mesh_terms: D000367:Age Factors; D000428:Alcohol Drinking; D004249:DNA Damage / Q000235:genetics*; D000067565:Farmers / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008214:Lymphocytes / Q000187:drug effects; D008297:Male; D016273:Occupational Exposure / Q000032:analysis*; D010575:Pesticides / Q000032:analysis / Q000633:toxicity*; D012737:Sex Factors; D012907:Smoking; D016615:Telomere / Q000378:metabolism*; D059506:Telomere Shortening / Q000187:drug effects* / Q000235:genetics
chemical_list: D010575:Pesticides
keywords: Nucleoplasmic bridges; Occupational exposure; Pesticides; Relative telomere length