Early developmental anomalies in zebrafish (Danio rerio) embryos induced by the Clematis florida Thunb.

The C.florida. is one of the common medicines used by She population in China, with therapeutic effects of promoting blood circulation and anti-inflammatory. According to the acute toxicity grading standard of chemical substances, this herb is a low-toxicity herb. At present, the safety of C.florida. , especially its impact on early embryonic development, is still unclear. This study investigated the toxic effects of C. florida. on early embryonic development using a zebrafish embryo model. In this study, we used zebrafish embryos exposed to C.florida. at early stage to assess the early developmental toxicity by analyzing the developmental toxicity phenotype, oxidative stress, cell apoptosis, total enzyme activity, behavioral trajectory, and gene expression levels. Embryos of the zebrafish exposed to different concentrations of C.florida. exhibited multiple organs and systems developmental disorders, including the heart, vessels, brain, bone, liver, and so on. Especially, with the increase of drug concentration, it is observed that the developmental malformations of the cardiovascular structure and function in larvae are becoming increasingly severe. In addition, results show that the abnormalities in embryonic development may be attributed to oxidative stress induced by apoptosis and activation of immune system resulting from an imbalance in the hematopoietic system. This study provides a comprehensive and detailed summary of the toxic effects of C.florida. on embryonic development, which contributes to a deeper understanding of the potential adverse developmental consequences, and also prompt people to pay considerable attention to its treatment in medicinal practice. • C.florida. has toxic effects on early embryonic development. • Toxic effects manifest as dose-dependent developmental inhibition of multiple systems. • C.florida. causes Cytotoxicity caused by oxidative stress imbalance. • The clinical application of C.florida. needs to be more cautious.