DNA damage assessment in peripheral blood of Swiss albino mice after combined exposure to volatile anesthetics and 1 or 2 Gy radiotherapy in vivo

Abstract

Purpose

Patient immobilization by general volatile anesthesia (VA) may be necessary during medical radiology treatment, and its use has increased in recent years. Although ionizing radiation (IR) is a well-known genotoxic and cytotoxic agent, and VA exposure has caused a range of side effects among patients and occupationally exposed personnel, there are no studies to date comparing DNA damage effects from combined VA and single fractional IR dose exposure.

Material and methods

We investigate whether there is a difference in white blood cells DNA damage response (by the alkaline comet assay) in vivo in 185 healthy Swiss albino mice divided into 37 groups, anesthetized with isoflurane/sevoflurane/halothane and exposed to 1 or 2 Gy of IR. Blood samples were taken after 0, 2, 6 and 24 h after exposure, and comet parameters were measured: tail length, tail intensity and tail moment. The cellular DNA repair index was calculated to quantify the efficiency of cells in repairing and re-joining DNA strand breaks following different treatments.

Results

In combined exposures, halothane caused higher DNA damage levels that were dose-dependent; sevoflurane damage increase did not differ significantly from the initial 1 Gy dose, and isoflurane even demonstrated a protective effect, particularly in the 2 Gy dose combined exposure. Nevertheless, none of the exposures reached control levels even after 24 h.

Conclusion

Halothane appears to increase the level of radiation-induced DNA damage, while sevoflurane and isoflurane exhibited a protective effect. DNA damage may have been even greater in target organs such as liver, kidney or even the brain, and this is proposed for future study.

Keywords:

• Alkaline comet assay
• halothane
• isoflurane
• sevoflurane
• Swiss albino mice

Acknowledgement

The authors would like to thank Prof Makso Herman for proofreading the manuscript.

Disclosure statement

The authors report no conflicts of interest.

Additional information

Notes on contributors

Vesna Benković

Vesna Benković, PhD, Full professor at the Division of Animal physiology on Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia

Nikola Borojević

Nikola Borojević, MD, Radiologist, Warrington and Halton Teaching Hospitals NHS Foundation Trust, Lovely Ln, Warrington WA5 1QG, United Kingdom

Dunja Šikić

Dunja Šikić, mag. biol. exp. Assistant at the Division of Animal physiology on Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia

Anica Horvat Knežević

Anica Horvat Knežević, Expert Advisor at the Division of Animal physiology on Department of Biology, Faculty of Science, University of Zagreb, Zagreb, Croatia

Mirta Milić

Mirta Milić, PhD, Senior research associate at the Mutagenesis Unit in Institute for Medical Research and Occupational Health, Zagreb, Croatia