Assessment of developmental delay in the zebrafish embryo teratogenicity assay

Abstract

In this study we analyzed some aspects of the assessment of developmental delay in the zebrafish embryotoxicity/teratogenicity test and explored the suitability of acetylcholinesterase (AChE) activity as a biochemical marker and as a higher throughput alternative to morphological endpoints such as head-trunk angle, tail length and morphological score. Embryos were exposed from 4 to 52 h post-fertilization (hpf) to a selection of known embryotoxic/teratogen compounds (valproic acid, retinoic acid, caffeine, sodium salicylate, glucose, hydroxyurea, methoxyacetic acid, boric acid and paraoxon-methyl) over a concentration range. They were evaluated for AChE activity, head-trunk angle, tail length and several qualitative parameters integrated in a morphological score. In general, the different patterns of the concentration-response curves allowed distinguishing between chemicals that produced growth retardation (valproic and methoxyacetic acid) and chemicals that produced non-growth-delay related malformations. An acceptable correlation between the morphological score, AChE activity and head-trunk angle as markers of developmental delay was observed, being AChE activity particularly sensitive to detect delay in the absence of malformations.

Developmental profiling of ASD-related shank3 transcripts and their differential regulation by valproic acid in zebrafish

“…The concentrations that caused teratogenic effects, as detailed in the literature, varied among studies but generally ranged from 0.1 to 3.0 mM (Li et al, 2009; Selderslaghs et al, 2009; Brannen et al, 2010; Terbach et al, 2011; Cowden et al, 2012; Teixido et al, 2013). Thus, an initial dose-response experiment was conducted to determine the effects of two different VPA concentrations, 1 and 0.5 mM, on zebrafish embryos (Fig.…”

Comparative toxicity of lead (Pb2+), copper (Cu2+), and mixtures of lead and copper to zebrafish embryos on a microfluidic chip

“…The average mortality of the control (the 17 chamber) was 8. of C1, C24, C23, C22, C21, C20, C19, and C18 in turn) or Cu 2þ (concentration from high to low of C9, C10, C11, C12, C13, C14, C15, and C16 in turn) solution, but there is no significant difference at the low concentration (Pb 2þ , 18,19,20;Cu,14,15,16). The mortality of mixture solution (Pb 2þ and Cu 2þ (C2-C8)) was obviously higher than the control group ( Fig.…”

“…16 The fish were kept on a 14 h light/10 h dark circle and the water temperature was set at 26 6 1 C. 17 Constant filtering or constant flow-through conditions ensured that ammonia, nitrite, and nitrate were kept below the detection limits, which were 0-5, 0.025-1, and 0-140 mg l…”

From cutting edge to guideline: A first step in harmonization of the zebrafish embryotoxicity test (ZET) by describing the most optimal test conditions and morphology scoring system

“…: lasting until 48-52 hpf [19,33], until 72-80 hpf [11,12], until 96 hpf [20,22] until 120 hpf [4,8,9,14,34] or until 144 hpf [30]. It can be argued that some compounds would need specific embryonic stages to elicit their teratogenic effects, especially if specific receptors/targets need to be present to elude the teratogenic effect.…”

“…Multiple teratogenicity scoring systems have been developed with good predictability rates [2,8,12,13,19,21,22,33]. For most of these papers, only limited information is given on the exact method used.…”