Environmental contamination by antibiotics has become a global issue. Colistin, a cationic antimicrobial polypeptide, has been widely used in human/veterinary medicine, and growth promotion in aquaculture. However, no study has been conducted to test the toxic effects of colistin on aquatic animals. In this study, we examined the effects of colistin on zebrafish embryos. Zebrafish embryos were incubated in different concentrations (0, 0.01, 0.1, 1, 2, 3, and 10 μM) of colistin for 96 h. Colistin increased the mortality rate in a dose-dependent manner (LC₅₀ was 3.0 μM or 3.5 mg L^-1), but it did not change the hatching rate, heart rate, body length, eye size, or yolk size of embryos. However, colistin impaired keratinocytes and lateral-line hair cells in the skin of embryos. Colistin (at concentrations ≥0.1 μM) decreased the number of FM1-43-labeled hair cells and reduced the mechanotransduction-mediated Ca²⁺ influx at hair bundles, suggesting that sublethal concentrations of colistin can impair lateral line function. To investigate the lethal injury, morphological changes were sequentially observed in post-hatched embryos subjected to lethal concentrations of colistin. We found that skin keratinocytes were severely damaged and detached after exposure, leading to hypotonic swelling of the yolk sac, loss of ion contents, cell lysis, and eventual death. This study revealed that acute colistin exposure can impair skin cells and pose a threat to fish survival.

抗生素对环境的污染已成为全球性问题。共价素是一种阳离子抗微生物多肽，已广泛用于人/兽药以及促进水产养殖的生长。但是，尚未进行测试大肠粘菌素对水生动物的毒性作用的研究。在这项研究中，我们检查了粘菌素对斑马鱼胚胎的影响。斑马鱼胚胎在粘菌素的不同浓度（0、0.01、0.1、1、2、3和10μM）中孵育96小时。Colistin以剂量依赖性方式增加死亡率（LC ₅₀为3.0μM或3.5 mg L ^-1），但是它并没有改变孵化率，心率，体长，眼睛大小或卵黄大小。但是，大肠菌素会损害胚胎皮肤中的角质形成细胞和侧线毛细胞。Colistin（浓度≥0.1μM）减少了FM1-43标记的毛细胞数量，并减少了机械转导介导的Ca ²⁺流入发束，表明粘菌素的致死浓度可能会损害侧线功能。为了研究致死性损伤，在受到致死菌素浓度致死的孵化后胚胎中顺序观察到形态变化。我们发现，皮肤角质形成细胞在暴露后会严重受损和脱离，从而导致卵黄囊低渗性肿胀，离子含量降低，细胞溶解以及最终死亡。这项研究表明，急性粘菌素暴露会损害皮肤细胞并威胁鱼类生存。