Radioadaptive Response Induced by Alpha-Particle-Induced Stress Communicated in Vivo between Zebrafish Embryos

Abstract

We report data demonstrating that zebrafish embryos irradiated by alpha particles can release a stress signal into the water, which can be communicated to the unirradiated zebrafish embryos sharing the same water medium and thereby inducing a radioadaptive response in these unirradiated zebrafish embryos. The effects of radiation on the whole embryos were studied through quantification of apoptotic signals at 24 h post fertilization through staining with the vital dye acridine orange, followed by counting the stained cells under a microscope. In these experiments, dechorionated embryos were irradiated and then partnered with two other groups of unirradiated embryos, namely the bystander group (no more further treatments) and adaptive group (subjected to a further challenging dose) of embryos. The adaptive group of embryos were then separately further irradiated with a challenging dose. The results show that the number of apoptotic signals for the adaptive group is smaller than that for the corresponding control group, while that for the bystander group is larger than that for the corresponding control group. These suggest that the stress communicated in vivo between the irradiated zebrafish embryos and those unirradiated embryos sharing the same medium will induce radioadaptive response in the unirradiated embryos.

Low Doses of Gamma-Irradiation Induce an Early Bystander Effect in Zebrafish Cells Which Is Sufficient to Radioprotect Cells

“…The strength of the rescue effect depends on the number of rescuing unirradiated bystander embryos [33], [34], [35]. Based on these studies, radioadaptation experiments were done on embryonic ZF4 cells (see Figure 6 for experimental set up).…”

Embryonic ionizing radiation exposure results in expression alterations of genes associated with cardiovascular and neurological development, function, and disease and modified cardiovascular function in zebrafish

“…Previous studies using the zebrafish model system to evaluate ionizing radiation exposure have been used to assess general toxicity (e.g., mortality, hatching rates, gross morphological alterations, DNA damage, and apoptosis) (e.g., Bladen et al, 2007; Choi et al, 2010a,b, 2012a, 2013; Pereira et al, 2011; Sorrells et al, 2012; Yu et al, 2012; Toruno et al, 2014), to screen radiation protectors (McAleer et al, 2005; Geiger et al, 2006), and to assess the long-term effects on liver gene expression (Jaafar et al, 2013). To the best of our knowledge, no work is published on the effect of IR to heart rate using the zebrafish model.…”

Embryos of the zebrafish Danio rerio in studies of non-targeted effects of ionizing radiation

“…Yum et al [215] reported the communication of alpha-particle-induced bystander signals between 1.5 hpf zebrafish embryos. Choi et al [229,230] further demonstrated that the RIBE communication between zebrafish embryos in vivo could actually induce the RAR against a challenging dose and induce a hormetic effect, respectively, in partnered unirradiated zebrafish embryos sharing the same medium with irradiated embryos. Moreover, unirradiated bystander zebrafish embryos were found to release a feedback signal back to the irradiated zebrafish embryos, which lead to a mitigation of the effects of radiation in the irradiated embryos [231].…”