Simultaneous quantification of T4, T3, rT3, 3,5‐T2 and 3,3′‐T2 in larval zebrafish (Danio rerio) as a model to study exposure to polychlorinated biphenyls

• DOI: 10.1002/bmc.4185
• Publication Date: 2018-01-04T00:32:48Z
• Authors: Xiaopeng Chen; Kyla M. Walter; Galen W. Miller; Pamela J. Lein; Birgit Puschner
• Keywords: 0301 basic medicine; 570; Thyroid Hormones; Endocrine Disruptors; 01 natural sciences; Analytical Chemistry; 03 medical and health sciences; Limit of Detection; Tandem Mass Spectrometry; 615; derivatization; Animals; PCBs; Chromatography, High Pressure Liquid; Zebrafish; thyroid hormones; Chromatography; Biomedical and Clinical Sciences; Animal; Reproducibility of Results; Pharmacology and Pharmaceutical Sciences; zebrafish; Polychlorinated Biphenyls; 0104 chemical sciences; Disease Models, Animal; Pharmacology and pharmaceutical sciences; UPLC-MS/MS; High Pressure Liquid; Larva; Chemical Sciences; Disease Models; Linear Models; Analytical chemistry

AbstractEnvironmental toxicants that interfere with thyroid hormone (TH) signaling can impact growth and development in animals and humans. Zebrafish represent a model to study chemically induced TH disruption, prompting the need for sensitive detection of THs. Simultaneous quantification of 3,3′,5‐triiodo‐l‐thyronine (T3), thyroxine (T4), 3,3′,5′‐triiodo‐l‐thyronine (rT3), 3,5‐diiodo‐l‐thyronine (3,5‐T2) and 3,3′‐diiodo‐l‐thyronine (3,3′‐T2) in zebrafish larvae was achieved by ultra‐performance liquid chromatography–tandem mass spectrometry in positive ion mode. Solid‐phase extraction with SampliQ cartridges and derivatization with 3 m hydrochloric acid in n‐butanol reduced matrix effects. Derivatized compounds were separated on an Acquity UPLC BEH C18 column with mobile phases consisting of 0.1% acetic acid in deionized water and 0.1% acetic acid in methanol. The limits of detection ranged from 0.5 to 0.6 pg injected on column. The method was validated by evaluating recovery (77.1–117.2%), accuracy (87.3–123.9%) and precision (0.5–12.4%) using diluted homogenized zebrafish embryos spiked with all target compounds. This method was then applied to zebrafish larvae collected after 114 h of exposure to polychlorinated biphenyls (PCBs), including PCB 28, PCB 66 and PCB 95, or the technical mixture Aroclor 1254. Exposure to PCB 28 and PCB 95 increased the T4:T3 ratio and decreased the T3:rT3 ratio, demonstrating that this method can effectively detect PCB‐induced alterations in THs.