DNA damage and circulating cell free DNA in greenhouse workers exposed to pesticides

Abstract

Pesticides widely used in agriculture and other applications have been linked to cancer and other diseases through several potential mechanisms. The goals of this study were to assess DNA damage in lymphocytes by the cytokinesis-block micronucleus assay (CBMN), and to measure circulating cell free DNA (ccf-DNA) in the blood of pesticide-exposed greenhouse workers and matched controls living in the same area. CBMN was applied to peripheral blood lymphocyte samples taken at different times (spring and autumn) for each individual. We measured plasma ccf-DNA levels using a Qubit fluorometer. The results indicated that the MNL, BNMN, and NBUDs frequencies of pesticide-exposed individuals were significantly higher than non-exposed individuals. Apart from MNL, BNMN and CBPI, a season-related effect was found for the NPB and NBUD frequencies. With MNL and BNMN as the dependent variables, multiple regression analysis showed that age and gender affected MN formation. The ccf-DNA level in the pesticide-exposed group was significantly higher than the control group. There was no seasonal variation regarding the free DNA amount. Ccf-DNA in males was found to be higher than females. The MNL, BNMN, NPB, and CBPI did not correlate with the ccf-DNA amount. It can be concluded that pesticide exposure can modulate DNA integrity via different mechanisms. Also, elevated levels of ccf-DNA could be recommended as a biomarker of pesticide exposure. Environ. Mol. Mutagen. 59:161-169, 2018. © 2017 Wiley Periodicals, Inc.

DNA Damages in Patients with Congenital Hearing Loss

“…We found a positive correlation between the MN and NBUD formation in the patients. A similar correlation was observed in previous studies (7,8). We could suggest that there might be a common mechanism for the formation of MN and NBUD in the patients with hearing loss.…”

“…The CBMN assay was applied to the blood samples to determine the frequency of MN, NPB, and NBUD in both groups ( Figure 2). The method was carried out as described by Fenech (6) and routinely used by our group (7,8). Five ml of the blood sample was taken from each donor in a sterile heparinized tube for all the participants.…”

Biospecimen Science of Blood for cfDNA Genetic Analyses

“…The same circadian rhythmicity, with higher cfDNA levels at mid-day, was observed in colorectal cancer patients of stages I-III, but not stage IV [26]. Environmental exposures, such as exposure to pesticides, may influence the levels of cfDNA; these levels were found to be higher in males than in females [27]. Finally, age is a significant covariable when one studies relative cfDNA amounts at specific genomic locations, such as transcription start and termination sites, or cfDNA-associated methylation signals, corresponding to different tissue types [28] (Fig.…”

The influence of biological and lifestyle factors on circulating cell-free DNA in blood plasma

“…In patient cohorts and workers exposed to occupational hazards, most studies (21/24) report no differences in cirDNA between males and females. A single study of 72 greenhouse workers reported higher cirDNA level in males ( Çayir et al, 2018 ), but the remaining two patient studies reported higher cirDNA in females ( Karlas et al, 2017 ; Kim et al, 2014 ). However, of these, one analysis, conducted in 30 gastric patients, had imbalanced sample numbers with 23 males and only 7 females ( Kim et al, 2014 ), while the other only saw the association with long cirDNA fragments (222 bp), with no effect on short fragments (90 bp) ( Karlas et al, 2017 ).…”