Developmental Toxicity of Diethylnitrosamine in Zebrafish Embryos/Juveniles Related to Excessive Oxidative Stress

Abstract

Diethylnitrosamine (DEN) is present in food, water, and daily supplies and is regarded as a toxicant of carcinogenicity. The developmental toxicity of DEN has been rarely reported as yet. In this study, zebrafish were exposed to different concentrations of DEN at 6 h post-fertilization (hpf) to access embryonic toxicity of the compound. The results show that DEN resulted in negative effects of hatching rate, heartbeat, body length, and spontaneous movement. Deformities, including notochord malformation, pericardium edema, embryonic membrane turbidity, tail hypoplasia, yolk sac deformity, and growth retardation, happened during exposure period. Moreover, production of reactive oxygen species (ROS) significantly increased after DEN treatment. Then, alterations of the expression level of oxidative stress-related genes were observed in our results. To our knowledge, this is the first study concerning the effect of DEN on zebrafish. And from the information of our research, we speculated that development toxicity of DEN should be related to the excessive oxidative stress.

Systematic Assessment of Exposure Variations on Observed Bioactivity in Zebrafish Chemical Screening

“…Others suggest that the plasma membrane and syncytial layers between the developing embryo and the chorion may play a role in reducing the uptake of chemical agents into embryo tissue [ 39 ]. Many chemicals have also been shown to affect hatching ability, including 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD), benzene [ 40 ], trichloroethylene [ 41 ], and diethylnitrosamine [ 42 ], potentially by weakening or paralyzing the fish, or by prohibiting the production of choriolytic enzymes naturally produced to degrade the chorion. This delay or inhibition of hatching could explain malformations later in development for some compounds.…”

Zebrafish larvae as a toxicity model in plasma medicine

“…In general, oxidants are known to disrupt the normal developmental processes of zebrafish embryos, leading to gross morphological defects. [ 63 ] We here report a subtle, but significant, change in morphology in some zebrafish larvae hatching from plasma‐treated eggs. This may point to sublethal alterations in embryonal development, which may not only be related to plasma‐derived ROS but also other plasma components present during direct treatment such as electric fields and UV radiation [ 64 ] that could potentially disrupt embryonic development.…”

A new aminoglycoside etimicin shows low nephrotoxicity and ototoxicity in zebrafish embryos

“…We noticed that a number of embryos demonstrate delayed hatching after AG exposure. Hatching, corresponding to the release of an individual from the egg envelope (or chorion) to a free‐living individual, has been shown to be sensitive to a variety of chemical reagents (Huang et al, 2018; J. Li et al, 2018). It is one of important indices with which to evaluate embryo toxicity in zebrafish.…”