The effects of x-ray radiation on the eye development of zebrafish

Abstract

<jats:p> The toxic effects of x-ray radiation on eye development was measured using zebrafish as a model organism. Zebrafish embryos at 8 h post-fertilization (hpf) were irradiated using X-rays at doses of 1, 2, 4, and 8 Gy. At 24 and 48 hpf, x-ray radiation induced a significant increase in reactive oxygen species (ROS) content and cell apoptotic signals. Both of these increases were dose dependent and there were significant positive relationships between them at 24 hpf. At 48 and 72 hpf, the increase of ROS concentration can be eliminated by increasing activities of superoxide dismutase and catalase. Although the ROS generated by x-ray radiation caused a significant increase in cell apoptosis at 24 and 48 hpf, the cellular layers of the retina and lens formation in the irradiated groups were not significantly disrupted at 144 hpf compared with the control group, with the exception of a heterogeneous distribution of the cells in inner nuclear cell layer and a significant decrease in the diameters of whole eyes after 8 Gy irradiation. X-Ray radiation at later stages of gastrulation may not cause distinct optic complications; however, there is still a risk of microophthalmia at high doses of irradiation. </jats:p>

Radioprotective agents to prevent cellular damage due to ionizing radiation

“…Ionizing radiation is widely used in medical diagnostics, cancer-related therapy, and has additional industrial applications [ 7 ]. Known hazards associated with human exposure to ionizing radiation include: induction of cellular death, genetic mutations, and carcinogenesis [ 7 ]. In addition to direct cellular effects, radiation exposure can also damage cells through the generation of reactive oxygen species (i.e.…”

“…Reactive oxygen species (ROS) are formed when ionizing radiation is absorbed by small molecules, primarily water, surrounding cellular bio-macromolecules. These ROS react with cellular contents, including DNA and proteins [ 7 ].…”

“…Administering radioprotective agents has been proposed as one way to decrease radiation-related deleterious effects on cells. Antioxidants have the potential to act as free radical scavengers, and thus reduce some DNA damage caused by ionizing radiation [ 4 , 7 , 9 , 10 ]. Theoretically, this intervention would allow cellular defenses to keep pace with the free radicals generated by radiation exposure (assuming the intracellular level of antioxidants is sufficient at the time of radiation exposure).…”

Dose-dependent Changes After Proton and Photon Irradiation in a Zebrafish Model

“…Furthermore, our measurements detected a notable reduction in body length, which suggests spinal cord curvature and growth delay. It is well known that different radiation qualities cause developmental deteriorations (41)(42)(43)(44), but only a few studies measured the degree of spinal curvature (19,20) and confirmed a linear dose dependent increase in severity on the fourth dpi at a dose level of 10 Gy or higher. Sayed and Mitani (45) showed spinal cord abnormality (body curvature) in the embryos of fish (Medaka) even after exposure to UV-A irradiation.…”

MITO-Luc/GFP zebrafish model to assess spatial and temporal evolution of cell proliferation in vivo

“…In additional experiments, 24 hpf embryos were irradiated using sub-lethal X-rays at different doses 54 . Luciferase activity of untreated, 1.8 Gy and 2.7 Gy treated embryos was measured in vitro, 6 h after irradiation.…”