Keywords :
ZET test, developmental toxicology, medicinal plants, epiboly
Abstract :
[en] Purpose: Traditional medicines which have been used in Vietnam for thousands of years are generally thought to have few or no side effects and are efficacious in curing specific health problems. However, according to recent research, several plants, which were thought to be harmless for decades, have been linked to toxicity. Therefore, in this study, we aim to assess the toxicological properties of some medicinal plants in Northern Vietnam using the zebrafish embryo as a screening model.
Methods: Medicinal plants extracts were prepared by incorporating in the design more standardized methods as the traditional ones, using water and ethanol solvents. After that, the zebrafish was chosen as a whole animal model to screen the toxicity of a specific extract. Zebrafish Embryotoxicity Toxicity (ZET) test was analyzed by exposing extracts to zebrafish embryos, which were monitored at specific times during 4 days for survival and the presence of developmental malformations.
Results: LC50 and EC50 index from the ZET test of 13 different plant extracts were measured at 4 dpf. KT05E, KT10H, KT12E were quite toxic to the aquatic animal with LC50 < 100 mg/l. KT09E, KT10E, KT10H, KT13E affected the embryos at the early stage, within 24 hpf. There was no lethality from KT11H, KT13H, KT14H, KT16H treatment. The screening results were divided into five subgroups: (i) no toxicity and no malformation, (ii) edema and hemostasis (related to anti-angiogenesis), (iii) developmental retardation, (iv) mix malformation and (v) severe toxicity but no malformation. The remarkable result of the study was the effect of KT09 ethanol extract. In KT09E treatment, the development of embryos remained at the stage of 20-24 hpf, even after 4 dpf. This could be due to the regression cell movement in the development process from epiboly to full oblong.
