Malformations and mortality in zebrafish early stages associated with elevated caspase activity after 24  h exposure to MS-222.

Malformations and mortality in zebrafish early stages associated with elevated caspase activity after 24 h exposure to MS-222. Toxicol Appl Pharmacol. 2020 Dec 25;:115385 Authors: Félix LM, Luzio A, Antunes L, Coimbra AM, Valentim A Abstract Tricaine methanesulfonate (MS-222) is a commonly used anaesthetic agent for immobilization of aquatic species. However, delayed development and malformations have been observed in 24 hpf (hours post-fertilization) zebrafish embryos after long-term immobilization. Still, no comprehensive study has been described regarding zebrafish exposure to MS-222 during the first hours of development, which are one of the most sensitive life stages to toxicants. Therefore, this research aimed to assess the toxicity of a 24 h exposure to MS-222 on zebrafish embryonic development. Based on the MS-222 LC50, early blastula stage embryos (~2 hpf) were exposed to 0, 12.5, 25 and 50 mg L-1 for 24 h and then allowed to develop up to 144 hpf. The chromatographic analysis showed that this anaesthetic agent bioaccumulates in 26 hpf zebrafish larvae in a concentration-dependent manner. In addition, increased mortalities and skeletal abnormalities were observed at 144 hpf, namely in the highest tested concentration. Yet, no craniofacial anomalies were observed either by alcian blue or calcein staining methods. Independently of the tested concentration, decreased speed and distance travelled were perceived in 1...
Source: Toxicology and Applied Pharmacology - Category: Toxicology Authors: Tags: Toxicol Appl Pharmacol Source Type: research