Search

To explore the developmental toxicity of cefixime (CE) in the developmental disorder and toxicity mechanism of CE on otic vesicles, zebrafish embryos were used as an animal model. The results showed that CE increased mortality in a dose-dependent manner and decreased the hatching rate of zebrafish larva at 96 hpf. Interestingly, CE significantly reduced the area of the saccule and utricle, as well as the area of otic vesicles in zebrafish larvae (p < 0.001). Fibroblast growth factor 8a (Fgf8a) inhibitors and bone morphogenetic protein (BMP) inhibitors caused similar morphological changes. CE decreased the lateral hair cells of zebrafish larvae in a dose-dependent manner. Furthermore, CE caused the downregulation of cartilage and bone-related genes and Na+/K+-ATPase-related genes of zebrafish larvae at 72 hpf and 120 hpf according to RT-qPCR. A comparison with the control group revealed that 100 μg/mL CE also caused a decrease in Na+/K+-ATPase activity (p < 0.01). In addition, antibody staining verified that CE inhibited the expression of Na+/K+-ATPase in the otic vesicles and the nephridium of zebrafish larvae. The data obtained in this study suggested that CE has significant ototoxicity during embryonic development of zebrafish, which is closely related to Na+/K+-ATPase and the regulation of the Fgf8a / BMP signaling pathways. The effects and toxicity of CE on ear development in other animal models need to be further explored. [Display omitted] • Cefixime inhibited the development of zebrafish otic vesicles. • Cefixime reduced the neuromasts cells of zebrafish larvae. • Cefixime down-regulated Na+/K+-ATPase and bone development-related genes. • Cefixime reduced the expression of Na+/K+-ATPase activity and protein expression. [ABSTRACT FROM AUTHOR]

This study aimed to explore behavioral changes of embryonic and larval zebrafish caused by pseudoephedrine hydrochloride (PSE) and its underlying mechanism. Zebrafish embryos were exposed to 0.5 µM, 2 µM, and 8 µM PSE at 4 h post-fertilization (4 hpf) or 22–23 hpf. Mortality, hatching rate, coiling frequency, heart rate, behavior changes, and related gene expression were observed at different developmental stages. PSE below 8 µM did not affect zebrafish mortality, hatching rate, and heart rate compared with the control group. For embryos, PSE caused an increase at 16–32 hpf in zebrafish coiling frequency which could be rescued by serotonin antagonist WAY100635. Similarly, PSE caused an increase in the swimming distance of zebrafish larvae at 120 hpf. PSE also elevated the expression of serotonin (5-HT)-related genes 5-htr1ab and tph2 and dopamine-related gene dbh. Behavioral changes in zebrafish embryos and larvae caused by PSE may be closely associated with increased expression of 5-HT and dopamine-related genes. This may be reflected that the behavioral changes in zebrafish are a possible PSE monitoring indicator. [ABSTRACT FROM AUTHOR]