No influence of serotonin levels in foetal bovine sera on radiation-induced bystander effects and genomic instability

Abstract

Purpose: The aim of this study was to contribute to an inter-laboratory investigation within the Non-Targeted Effects of Ionising Radiation Integrated project (NOTE) (2006–2010) to investigate the role of serum serotonin concentration on radiation-induced bystander effects using our successful experimental design. Two sera of high and low serotonin levels were tested alongside standard serum used in our laboratory.

Materials and methods: Primary Human Fibroblast 19 (HF19) cells were sham/irradiated with 0.5 Gy alpha-particles, in medium supplemented with serum of different levels of serotonin. Filtered medium was transferred to unirradiated HF19 bystander cells. Cells from irradiated and bystander populations were harvested for chromosomal analysis at early and delayed times post-irradiation/media transfer to assess initial damaging effects and induction of delayed chromosomal instability respectively.

Results: Chromosomal damage was elevated to significant levels (p = ≤ 0.005) above respective controls in both cell populations in all groups. Induction of delayed chromosomal instability was significantly observed in all groups at delayed time post irradiation/medium transfer. Furthermore, induction of bystander effects at early and delayed times was not significantly different between groups.

Conclusions: No effect of serotonin on the induction of either bystander effects of genomic instability was observed using this experimental system.

Keywords::

• Ionizing radiation
• human fibroblasts
• bystander effects
• genomic instability

Acknowledgements

We would like to thank Dr James Thompson, Gray Institute for Radiation Oncology and Biology, University of Oxford, UK, for alpha-particle irradiations.

Declaration of interest

The authors report no declaration of interest. The authors alone are responsible for the content and writing of the paper.

This work was funded as part of NOTE (Non Targeted Effects of Ionising Radiation Integrated project): 036465-F16R FP6 program.