Influence of chlorpyrifos exposure on UVB irradiation induced toxicity in human skin cells

Krzysztof Sawicki; Magdalena Matysiak-Kucharek; Marcin Kruszewski; Paulina Wojtyła-Buciora; Lucyna Kapka-Skrzypczak

doi:10.1186/s12995-023-00391-5

Influence of chlorpyrifos exposure on UVB irradiation induced toxicity in human skin cells

J Occup Med Toxicol. 2023 Oct 6;18(1):23. doi: 10.1186/s12995-023-00391-5.

Authors

Krzysztof Sawicki¹, Magdalena Matysiak-Kucharek², Marcin Kruszewski^{2

3}, Paulina Wojtyła-Buciora⁴, Lucyna Kapka-Skrzypczak^{5

6}

Affiliations

¹ Department of Molecular Biology and Translational Research, Institute of Rural Health, Jaczewskiego 2, Lublin, 20-090, Poland. sawicki.krzysztof@imw.lublin.pl.
² Department of Molecular Biology and Translational Research, Institute of Rural Health, Jaczewskiego 2, Lublin, 20-090, Poland.
³ Institute of Nuclear Chemistry and Technology, Centre for Radiobiology and Biological Dosimetry, Warsaw, Poland.
⁴ Department of Social Medicine and Public Health, Calisia University, Kalisz, Poland.
⁵ Department of Molecular Biology and Translational Research, Institute of Rural Health, Jaczewskiego 2, Lublin, 20-090, Poland. lucynakapka@gmail.com.
⁶ World Institute for Family Health, Calisia University, Kalisz, Poland. lucynakapka@gmail.com.

Abstract

Background: Although chlorpyrifos (CPS) has been banned in many developed countries, it still remains one of the best-selling pesticides in the world. Widespread environmental and occupational exposure to CPS pose a serious risk to human health. Another environmental factor that can adversely affect human health is ultraviolet radiation B (UVB, 280-315 nm wave length). Here we attempt determine if exposure to CPS can modify toxic effects of UVB. Such situation might be a common phenomenon in agriculture workers, where exposure to both factors takes place.

Methods: Two skin cell lines; namely human immortalized keratinocytes HaCaT and BJ human fibroblasts were used in this study. Cytotoxicity was investigated using a cell membrane damage detection assay (LDH Cytotoxicity Assay), a DNA damage detection assay (Comet Assay), an apoptosis induction detection assay (Apo-ONE Homogeneous Caspase-3/7 Assay) and a cell reactive oxygen species detection assay (ROS-Glo H₂O₂ assay). Cytokine IL-6 production was also measured in cells using an ELISA IL-6 Assay.

Results: Pre-incubation of skin cells with CPS significantly increased UVB-induced toxicity at the highest UVB doses (15 and 20 mJ/cm²). Also pre-exposure of BJ cells to CPS significantly increased the level of DNA damage, except for 20 mJ/cm² UVB. In contrast, pre-exposure of HaCaT cells, to CPS prior to UVB radiation did not cause any significant changes. A decrease in caspase 3/7 activity was observed in HaCaT cells pre-exposed to 250 µM CPS and 5 mJ/cm² UVB. Meanwhile, no statistically significant changes were observed in fibroblasts. In HaCaT cells, pre-exposure to CPS resulted in a statistically significant increase in ROS production. Also, in BJ cells, similar results were obtained except for 20 mJ/cm². Interestingly, CPS seems to inhibited IL-6 production in HaCaT and BJ cells exposed to UVB (in the case of HaCaT cells for all UVB doses, while for BJ cells only at 15 and 20 mJ/cm²).

Conclusions: In conclusion, the present study indicates that CPS may contribute to the increased UVB-induced toxicity in skin cells, which was likely due to the induction of ROS formation along with the generation of DNA damage. However, further studies are required to gain better understanding of the mechanisms involved.

Keywords: Chlorpyrifos; DNA damage; Reactive oxygen species; Skin cells; UVB radiation.