The effect of the aquatic contaminants bisphenol-A and PCB-95 on the zebrafish lateral line

Abstract

Environmental toxicants such as bisphenol-A (BPA) and polychlorinated biphenyls (PCBs) are prevalent in our water supply, soil, and many food products and can profoundly affect the central nervous system. Both BPA and PCBs can disrupt endocrine signaling, which is important for auditory development and function, but the effect of these toxicants on the auditory periphery is not understood. In this study we investigated the effect of PCB-95 and BPA on lateral line development, function, and regeneration in larval zebrafish. The lateral line is a system of mechanosensory hair cells on the exterior of the fish that are homologous to the hair cells located in the mammalian inner ear. We found that PCB-95 had no effect on lateral line development or hair cell survival. BPA also did not affect lateral line development, but instead had a significant effect on both hair cell survival and regeneration. BPA-induced hair cell loss is both dose-and time-dependent, with concentrations of 1 μM or higher killing lateral line hair cells during a 24 hr exposure period. Pharmacologic manipulation experiments suggest that BPA kills hair cells via activation of oxidative stress pathways, similar to prior reports of BPA toxicity in other tissues. We also observed that hair cells killed with neomycin, a known ototoxin, failed to regenerate normally when BPA was present, suggesting that BPA in aquatic environments could impede innate regenerative responses in fishes. Collectively, these data demonstrate that BPA can have detrimental effects on sensory systems, both in aquatic life and perhaps in terrestrial organisms, including humans.

Urban stormwater runoff negatively impacts lateral line development in larval zebrafish and salmon embryos

“…Zebrafish robustly regenerate damaged hair cells, and toxicants such as copper and bisphenol-A negatively impact regenerative potential 29 , 36 . We therefore examined hair cell regeneration during exposure to stormwater.…”

“…The lateral line contributes to behaviors such as orientation to current (rheotaxis), which may be important for navigation and migration 25 , 26 . As a surface structure, the lateral line directly contacts compounds in the aquatic environment, and sensory hair cells are highly susceptible to many toxicants of both biomedical and environmental origins 27 – 29 . The lateral line in larval zebrafish is an excellent model system for toxicology studies, owing to the small size of the organism, rapid ex utero development, and high fecundity 30 .…”

“…The lateral line in larval zebrafish is an excellent model system for toxicology studies, owing to the small size of the organism, rapid ex utero development, and high fecundity 30 . The zebrafish lateral line is a tractable model system for toxicology studies, contributing to our understanding of how aquatic pollutants such as copper and bisphenol-A affect fish sensory systems 29 , 31 – 33 .…”

Effect of Deepwater Horizon Crude Oil Water Accommodated Fraction on Olfactory Function in the Atlantic Stingray, Hypanus sabinus

“…Exposure to hydrocarbons and heavy metals, as well as pesticides and herbicides, is known to damage central or peripheral components of various sensory systems in teleost fishes 6 , 7 . Known effects include hypersensitivity of and damage to the lateral line 8 , 9 metal accumulation in the photoreceptor cells of the eye 10 , 11 , reduced eye pigmentation 12 , and altered olfactory structure and function 13 , 14 .…”

Sensory ecology of the fish lateral‐line system: Morphological and physiological adaptations for the perception of hydrodynamic stimuli

“…BPA-induced haircell loss was both dose and time-dependent, with concentrations of 1 μmol or higher killing lateral-line hair cells during a 24 h exposure period. Thus, bisphenol-A, which is contained in many plastic household products, can have detrimental effects on the lateral-line system and perhaps on other sensory systems (Hayashi et al, 2015).…”