Effects of 25 thyroid hormone disruptors on zebrafish embryos: A literature review of potential biomarkers

Zebrafish Embryonic Exposure to BPAP and Its Relatively Weak Thyroid Hormone-Disrupting Effects

“…Even at the phenotypic level, the TH-disrupting effects of BPAP were not confirmed in our study. Phenotypic endpoints were suggested as one of the components in the integrated approach for the suitable assessment of TH disruption [19]. A previous study suggested hatching, body length, eye impairment, morphological effects, and behavioral effects as indicators that should be monitored with the endpoints of TH disruption and demonstrated that these indicators show responses of 82%, 58%, 42%, 87%, and 69%, respectively, to substances that cause TH disruption [19]).…”

“…Phenotypic endpoints were suggested as one of the components in the integrated approach for the suitable assessment of TH disruption [19]. A previous study suggested hatching, body length, eye impairment, morphological effects, and behavioral effects as indicators that should be monitored with the endpoints of TH disruption and demonstrated that these indicators show responses of 82%, 58%, 42%, 87%, and 69%, respectively, to substances that cause TH disruption [19]). Bisphenol F, S, and Z, which have been used as BPA analogs similar to BPAP, also induced changes in the time to hatch or a reduced eyeball size ratio accompanied by a significant TH increase [3].…”

“…As a non-animal alternative model for chemical screening, zebrafish embryos can be used until the zebrafish starts to feed independently, which is at 5 d post fertilization (dpf) [17]. Despite morphological differences in its mature thyroid gland compared to higher vertebrates, the early steps in thyroid development of zebrafish show a significant resemblance [18,19]. From 70 to 80 h post fertilization (hpf), T4 synthesis in zebrafish embryo becomes detectable [19,20].…”

“…The aim of this study was to evaluate the integrated TH-disrupting effects of BPAP, including phenotypic endpoints (development and behavior). Based on a previous review, an integrated approach that included a combination of morphological, behavioral, and molecular process assessments appears to be the most suitable for facilitating an understanding of the TH-disrupting effects [19]. In addition, we compared the TH-disrupting potency of BPAP with that of BPA and other alternatives to determine whether BPAP is relatively safe.…”

Thyroid Disrupting Activities in Wastewater and Surface Waters: A Review of Their <i>in Vitro</i> Analyses

“…The hypothalamic-pituitary-gonad axis, and the hypothalamic-pituitary-thyroid axis are two major axes of the endocrine system that are particularly vulnerable to exogenous chemical assault owing to their delicate intricate cascade of cellular and molecular regulation of physiological functions [3] [4]. However, while the effects of EDCs on the HPG axis have been considerably investigated and comprehensively described, a lot remains to be clarified on the effect of EDCs on the HPT axis, principally involving the thyroid hormone system [5] [6].…”