Triphenyl phosphate-induced pericardial edema in zebrafish embryos is dependent on the ionic strength of exposure media. (February 2023)

• Record Type: Journal Article
• Authors: Wiegand, Jenna; Avila-Barnard, Sarah; Nemarugommula, Charvita; Lyons, David; Zhang, Sharon; Stapleton, Heather M.; Volz, David C.
• Is Part Of: Environment international. Volume 172(2023)
• Publication Date: 2023-02
• Subjects: Zebrafish -- Pericardial edema -- Osmoregulation -- Triphenyl phosphate -- Epithelium; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2023.107757
• Languages: English
• ISSNs: 0160-4120

Abstract

Graphical abstract: Highlights: Ionic strength of exposure media influences the severity of pericardial edema formation. D-Mannitol does not impact TPHP uptake in embryonic zebrafish, while preventing TPHP-induced pericardial edema formation. TPHP increases the frequency of microridges on the embryonic yolk sac epithelium. Abstract: Pericardial edema is commonly observed in zebrafish embryo-based chemical toxicity screens, and a mechanism underlying edema may be disruption of embryonic osmoregulation. Therefore, the objective of this study was to identify whether triphenyl phosphate (TPHP) – a widely used aryl phosphate ester-based flame retardant – induces pericardial edema via impacts on osmoregulation within embryonic zebrafish. In addition to an increase in TPHP-induced microridges in the embryonic yolk sac epithelium, an increase in ionic strength of exposure media exacerbated TPHP-induced pericardial edema when embryos were exposed from 24 to 72 h post-fertilization (hpf). However, there was no difference in embryonic sodium concentrations in situ within TPHP-exposed embryos relative to embryos exposed to vehicle (0.1% DMSO) from 24 to 72 hpf. Interestingly, increasing the osmolarity of exposure media with mannitol (an osmotic diuretic which mitigates TPHP-induced pericardial edema) and increasing the ionic strength of the exposure media (which exacerbates TPHP-induced pericardial edema) did not affect embryonic doses of TPHP, suggesting that TPHP uptake was not altered under these varying experimental conditions. Overall, our findings suggest that TPHP-induced pericardial edema within zebrafish embryos is dependent on the ionic strength of exposure media, underscoring the importance of further standardization of exposure media and embryo rearing protocols in zebrafish-based chemical toxicity screening assays.