Arismendi Nolberto, Caro Solange, Castro María Paz, Vargas Marisol, Riveros Gustavo, Venegas Tomas
Austral Biotech Research Center, Faculty of Science, Universidad Santo Tomás, Av. Ramón Picarte, Valdivia 1130, Chile.
Laboratories of Virology and Bee Pathology, Facultad de Agronomía, Universidad de Concepción, Av. Vicente Méndez, Chillán 595, Chile.
Insects. 2020 Jul 8;11(7):420. doi: 10.3390/insects11070420.
currently appears to be the predominant trypanosome in honey bees worldwide. Although, the specific effects of by single or mixed with other gut parasites such as on honey bees' health is still unclear. We consequently measured bees' survival, parasite loads, the expression of antimicrobial peptides (AMPs) and vitellogenin gene. Thus, (1) bees naturally infected with , (2) healthy bees inoculated with , (3) bees naturally infected with and inoculated with and (4) healthy bees (control) were maintained under controlled conditions. Honey bees infected with or with mixed infections of and had significantly lower survival rates than the control group at 20 days post-inoculation (dpi). A competitive suppression was also detected, provided that the load was significantly affected by the presence of at 15 dpi. Expressions of the AMPs defensin and hymenoptaecin rapidly (two hours post-inoculation) increased in bees infected with and mixed infections. However, this effect was not continuous. In fact, expressions of abaecin, defensin, hymenoptaecin and vitellogenin decreased drastically at 15 dpi in bees with both single and mixed infections. The decrease in the expression of AMPs and vitellogenin throughout this period was consistent with the reduced survivals observed in this study, indicating that mixed infections of and , and even into a scenario of competition between them, may have a synergic effect on the survival and immune-related gene expressions (biomarkers) of worker bees.
目前似乎是全球蜜蜂体内主要的锥虫。然而，单种感染或与其他肠道寄生虫（如 ）混合感染对蜜蜂健康的具体影响仍不清楚。因此，我们测量了蜜蜂的存活率、寄生虫载量、抗菌肽（AMPs）和卵黄原蛋白基因的表达。于是，将（1）自然感染 的蜜蜂、（2）接种 的健康蜜蜂、（3）自然感染 且接种 的蜜蜂以及（4）健康蜜蜂（对照组）置于可控条件下饲养。接种后20天（dpi），感染 或同时感染 和 的蜜蜂存活率显著低于对照组。还检测到了竞争性抑制作用，前提是在15 dpi时， 的载量受 的存在显著影响。在感染 和混合感染的蜜蜂中，抗菌肽防御素和膜翅目抗菌肽的表达在接种后迅速（两小时）增加。然而，这种效应并不持续。事实上，在单种感染和混合感染的蜜蜂中，abaecin、防御素、膜翅目抗菌肽和卵黄原蛋白的表达在15 dpi时急剧下降。在此期间，AMPs和卵黄原蛋白表达的下降与本研究中观察到的存活率降低一致，表明 和 的混合感染，甚至它们之间的竞争情况，可能对工蜂的存活和免疫相关基因表达（生物标志物）具有协同作用。
