Clothianidin induces DNA damage and oxidative stress in bronchial epithelial cells

Abstract

Clothianidin (CHN) is a member of the neonicotinoid group of insecticides. Its oxidative and DNA damage potential for human lung cells are not known. Therefore, the present study was designed to examine the effects of CHN on DNA damage and oxidative stress in human bronchial epithelial cells (BEAS‐2B) treated with CHN for 24, 72, and 120 hr. Our results indicate that CHN decreased cell viability in a concentration‐dependent manner. CHN induced DNA single‐strand breaks because alkaline comet parameters such as tail intensity, DNA in the tail, tail moment, and tail length increased. All CHN concentrations also significantly induced the formation of DNA double‐strand breaks (DSBs) because it increased phosphorylated H2AX protein foci for all treatment times and p53‐binding protein 1 foci for all treatments except for the lowest concentration (0.15 mM) of 120‐hr treatment. DNA damage caused by DNA DSBs was not repaired in a 24‐hr recovery period. CHN also induced oxidative stress by decreasing reduced glutathione and increasing lipid peroxidation. These results make it necessary to conduct studies about the detailed carcinogenic potential of CHN in humans because it can induce both oxidative and DNA damage.

Use of transcriptomics in hazard identification and next generation risk assessment: A case study with clothianidin

“…Of note, several studies additional to the regulatory studies mentioned in the Results section of this paper have been published regarding the genotoxic potential of CTD. No significant effect towards the Comet assay was observed in HepG2 human hepatoma cells, while CTD induced increase in tail intensity in neuronal SHSY-5Y and bronchial epithelial BEAS-2B cells ( Atli Sekeroglu et al, 2020 ; Senyildiz et al, 2018 ). Additionally, CTD induced the formation of DNA double strand breaks in BEAS-2B cells as evidenced by the increase in phosphorylated H2AX protein ( Atli Sekeroglu et al, 2020 ).…”

Increased DNA strand breaks and neoplastic transformation in human bladder cells treated with pioglitazone

“…After formation of DNA DSBs, H2AX is phosphorylated and gH2AX occurs in response to DNA damage. 53BP1, a well‐known DNA damage response protein, then binds to DSBs sites (Atlı Şekeroğlu et al ., 2020). Our neutral comet and immunofluorescence results of gH2AX and 53BP1 foci clearly showed that PIO induced DNA DSBs formation.…”

“…The cells were treated with eight concentrations of PIO (1, 2.5, 5, 10, 25, 50, 100, and 250 μM) for 24, 48, and 72 hr. MTT assay was performed as previously published (Atlı Şekeroğlu at el., 2020).…”

“…DNA single strand breaks (SSBs) and DNA double strand breaks (DSBs) were measured using alkaline and neutral comet assays as previously described (Qin et al ., 2014; Atlı Şekeroğlu et al ., 2020). After the nuclei of hTU1 cells with PIO were stained, comet images were captured using a Leica fluorescence microscope and analyzed with Comet Score 2.0 software (Tritek Corp, Sumerduck, VA).…”

“…The same recovery and positive control groups as in comet assay were created. Immunofluorescent staining and evaluation of foci were performed as previously published (Atlı Şekeroğlu et al ., 2020).…”