Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Minas Gerais 36570-900, Brazil.
Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa - campus Rio Paranaíba, Rio Paranaíba, Minas Gerais 38810-00, Brazil.
Sci Total Environ. 2022 Apr 1;815:152847. doi: 10.1016/j.scitotenv.2021.152847. Epub 2022 Jan 5.
The honey bee Apis mellifera is an important pollinator that increases the yield and quality of crops. In recent years, honey bee populations have declined in some parts of the world, which has been associated with several causes, including pesticides used in agriculture. Neonicotinoids are neurotoxic insecticides widely used in the world with systemic action mode contaminating nectar and pollen that may be consumed by bees. This study evaluated the side effects of imidacloprid in the midgut of A. mellifera after acute oral exposure. Toxicity, histopathology, cytotoxicity, and expression of autophagy-related gene atg1 were evaluated in honey bee workers orally exposed to imidacloprid. The estimated imidacloprid LC was 1.44 mg L. The midgut epithelium of bees fed on imidacloprid LC has the occurrence of cytoplasm vacuoles, enlarged intercellular spaces, disorganization of the striated border, and nuclear pyknosis, with an organ injury index that increases with time exposure. The midgut digestive cells of treated bees have apical protrusions, damaged mitochondria, and autophagosomes that were characterized for content with organelle debris and high expression of atg1. These features indicate the occurrence of high cell death in the midgut of workers exposed to imidacloprid, which may affect the digestibility the physiology of the insect.
蜜蜂是一种重要的传粉媒介，可以提高作物的产量和质量。近年来，世界上一些地区的蜜蜂数量有所下降，这与包括农业中使用的杀虫剂在内的多种原因有关。新烟碱类杀虫剂是一种具有全身作用模式的神经毒性杀虫剂，广泛用于污染可能被蜜蜂食用的花蜜和花粉。本研究评估了急性口服接触后吡虫啉对蜜蜂中肠的副作用。对经口摄入吡虫啉的蜜蜂工蜂进行了毒性、组织病理学、细胞毒性和自噬相关基因 atg1 表达的评估。估计吡虫啉 LC 为 1.44 mg/L。饲喂吡虫啉 LC 的蜜蜂中肠上皮细胞出现细胞质空泡、细胞间隙增大、纹状缘紊乱和核固缩，随着暴露时间的延长，器官损伤指数增加。处理过的蜜蜂中肠消化细胞有顶端突起、受损的线粒体和自噬体，这些自噬体含有细胞器碎片和 atg1 的高表达。这些特征表明，接触吡虫啉的工蜂中肠发生了高细胞死亡，这可能影响昆虫的消化功能和生理机能。
