Embryonic toxico-pathological effects of meglumine antimoniate using a chick embryo model

Leishmaniasis is one of the diverse and neglected tropical diseases. Embryo-toxicity of drugs has always been a major concern. Chick embryo is a preclinical model relevant in the assessment of adverse effects of drugs. The current study aimed to assess embryonic histopathological disorders and amniotic fluid biochemical changes following meglumine antimoniate treatment. The alteration of vascular branching pattern in the chick’s extra-embryonic membrane and exploration of molecular cues to early embryonic vasculogenesis and angiogenesis were also quantified. Embryonated chicken eggs were treated with 75 or 150 mg/kg of meglumine antimoniate. Embryo malformations, growth retardation and haemorrhages on the external body surfaces were accompanied by histopathological lesions in the brain, kidney, liver and heart in a dose-dependent manner. Significant rise occurred in the biochemical indices of alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase and amylase in the amniotic fluid. Quantification of the extra-embryonic membrane vasculature showed that the anti-angiogenic and anti-vasculogenic effects of the drug were revealed by a significant decrease in fractal dimension value and mean capillary area. The relative expression levels of vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 mRNA also significantly reduced. Concerns of a probable teratogenicity of meglumine antimoniate were established by data presented in this study. It is concluded that tissue lesions, amniotic fluid disturbance, altered early extra-embryonic vascular development and gene expression as well as the consecutive cascade of events, might eventually lead to developmental defects in embryo following meglumine antimoniate treatment. Therefore, the use of meglumine antimoniate during pregnancy should be considered as potentially embryo-toxic. Hence, physicians should be aware of such teratogenic effects and limit the use of this drug during the growing period of the fetus, particularly in rural communities. Further pharmaceutical investigations are crucial for planning future strategies.利什曼病（Leishmaniasis）是一类多样且被忽视的热带疾病。药物的胚胎毒性始终是学界关注的核心问题。鸡胚（chick embryo）是评估药物不良反应的经典临床前模型。本研究旨在探究葡甲胺锑（meglumine antimoniate）给药后胚胎的组织病理学异常与羊水中的生化指标变化，同时量化分析鸡胚胚外膜的血管分支模式改变，并检测早期胚胎血管发生与血管生成的分子标志物变化。实验中，研究人员以75 mg/kg与150 mg/kg的葡甲胺锑对受精鸡卵进行给药处理。结果显示，胚胎出现畸形、生长迟缓以及体表出血，同时伴随脑、肾、肝与心脏的组织病理学损伤，且上述病变均呈剂量依赖性特征。羊水中的碱性磷酸酶（alkaline phosphatase, ALP）、天冬氨酸氨基转移酶（aspartate aminotransferase, AST）、丙氨酸氨基转移酶（alanine aminotransferase, ALT）与淀粉酶（amylase）水平均出现显著升高。对胚外膜脉管系统的量化分析表明，该药物的抗血管生成与抗血管发生效应可通过分形维数与平均毛细血管面积的显著降低得以体现。血管内皮生长因子A（vascular endothelial growth factor A, VEGF-A）与血管内皮生长因子受体2（vascular endothelial growth factor receptor 2, VEGFR2）的mRNA相对表达水平同样出现显著下调。本研究数据证实了葡甲胺锑存在潜在致畸性，印证了此前的相关顾虑。研究结论表明，葡甲胺锑给药后引发的组织损伤、羊水稳态失衡、早期胚外血管发育异常、基因表达紊乱及后续级联反应事件，最终可能导致胚胎发育缺陷。因此，妊娠期间使用葡甲胺锑应被视为具有潜在胚胎毒性的行为。临床医师需警惕该药物的致畸效应，在胎儿发育阶段限制其使用，尤其在农村地区。未来需开展进一步的药学研究，以制定针对性的后续防控策略。