title: Hormetic effect induced by depleted uranium in zebrafish embryos.
abstract: The present work studied the hormetic effect induced by uranium (U) in embryos of zebrafish (Danio rerio) using apoptosis as the biological endpoint. Hormetic effect is characterized by biphasic dose-response relationships showing a low-dose stimulation and a high-dose inhibition. Embryos were dechorionated at 4h post fertilization (hpf), and were then exposed to 10 or 100μg/l depleted uranium (DU) in uranyl acetate solutions from 5 to 6 hpf. For exposures to 10μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20 hpf but were significantly decreased at 24 hpf, which demonstrated the presence of U-induced hormesis. For exposures to 100μg/l DU, the amounts of apoptotic signals in the embryos were significantly increased at 20, 24 and 30 hpf. Hormetic effect was not shown but its occurrence between 30 and 48 hpf could not be ruled out. In conclusion, hormetic effect could be induced in zebrafish embryos in a concentration- and time-dependent manner.
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Hong Kong.
authors.forename: C Y P
authors.initials: CY
authors.lastname: Ng
authors.affiliation: Department of Biomedical Sciences, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong. Electronic address: bhcheng@cityu.edu.hk.
authors.forename: S H
authors.initials: SH
authors.lastname: Cheng
authors.affiliation: Department of Physics and Materials Science, City University of Hong Kong, Hong Kong; State Key Laboratory in Marine Pollution, City University of Hong Kong, Hong Kong. Electronic address: peter.yu@cityu.edu.hk.
authors.forename: K N
authors.initials: KN
authors.lastname: Yu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004625:Embryo, Nonmammalian / Q000187:drug effects; D059165:Hormesis / Q000187:drug effects*; D014501:Uranium / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity; D015027:Zebrafish / Q000502:physiology*
chemical_list: D014874:Water Pollutants, Chemical; D014501:Uranium
keywords: Depleted uranium; Hormetic effect; Uranium; Zebrafish embryo