Effects of low dose radiation on behavior rhythm of zebrafish (Danio rerio)

Weichao Zhao; Liang Mao; Chuqi He; Dexin Ding; Nan Hu; Xiaohua Song; Dingxin Long

Ecotoxicology and Environmental Safety (Apr 2023)

Effects of low dose radiation on behavior rhythm of zebrafish (Danio rerio)

Weichao Zhao,
Liang Mao,
Chuqi He,
Dexin Ding,
Nan Hu,
Xiaohua Song,
Dingxin Long

Affiliations

Weichao Zhao: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Hunan Province Key Laboratory of Typical Evironmental Pollution and Health Hazards, Hengyang Medical School, University of South China, Hengyang 421001, PR China
Liang Mao: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Hunan Province Key Laboratory of Typical Evironmental Pollution and Health Hazards, Hengyang Medical School, University of South China, Hengyang 421001, PR China
Chuqi He: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Hunan Province Key Laboratory of Typical Evironmental Pollution and Health Hazards, Hengyang Medical School, University of South China, Hengyang 421001, PR China
Dexin Ding: Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy,University of South China, Hengyang, Hunan 421001, PR China
Nan Hu: Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy,University of South China, Hengyang, Hunan 421001, PR China
Xiaohua Song: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Hunan Province Key Laboratory of Typical Evironmental Pollution and Health Hazards, Hengyang Medical School, University of South China, Hengyang 421001, PR China
Dingxin Long: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Hunan Province Key Laboratory of Typical Evironmental Pollution and Health Hazards, Hengyang Medical School, University of South China, Hengyang 421001, PR China; Corresponding author at: School of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, PR China.

Journal volume & issue: Vol. 255
p. 114779

Abstract

Read online

Biological rhythm refers to the internal regulation of various life activities of an organism, which are determined by the specific time structure sequences of each individual. Behavior rhythm is the most intuitive embodiment of biological rhythm. To study the effect of low dose radiation on behavioral rhythm, zebrafish (Danio rerio) was used as a model organism in this study. The early embryos of zebrafish were irradiated at doses of 0.01, 0.1, and 1 Gy to observe the changes in zebrafish development, circadian rhythm, key clock genes, related RNA and protein expression, and melatonin. The results revealed that 0.1 and 1 Gy radiation could lead to different degrees of telencephalic nerve cell apoptosis and the formation of vacuolar structures. 0.1 and 1 Gy radiation could reduce the hatching rate of zebrafish embryos at 72 hpf and delay embryo hatching. The analysis of circadian behavior at 120 hpf demonstrated that 1 Gy dose of radiation altered the circadian rhythm of zebrafish, as well as decreased the distance, amplitude, and phase of movement. RT-PCR analysis of the key clock genes (bmal1b, clock1a, per1b, per2, cry2, and nr1d1) involved in regulating circadian rhythm was performed. The results showed that 1 Gy radiation could interfere with the expression of clock genes in zebrafish embryos and upregulate bmal1b, clock1a, and per1b. Western blot experiments further verified the protein expression of key clock genes, bmal1b and clock. Detection of melatonin secretion at different time points over 24 h showed that radiation doses of 0.1 and 1 Gy could increase melatonin secretion. Based on these findings, it is speculated that a certain dose of radiation may affect melatonin secretion, which impacts the telencephalon structure and ontogeny of zebrafish, delays hatching, and changes the circadian rhythm. This effect is thought to be achieved through upregulating the expression of circadian rhythm genes, clock1a and per1b and related proteins, which may be responsible for the abnormal circadian rhythm caused by radiation.

Published in Ecotoxicology and Environmental Safety

ISSN: 0147-6513 (Print); 1090-2414 (Online)
Publisher: Elsevier
Country of publisher: United States
LCC subjects: Technology: Environmental technology. Sanitary engineering: Environmental pollution; Geography. Anthropology. Recreation: Environmental sciences
Website: https://www.journals.elsevier.com/ecotoxicology-and-environmental-safety

About the journal

Abstract

Keywords