蜜蜂容易中毒,也被称为枣花病,从枣花中收集花蜜后,导致觅食者的混乱死亡。枣花病的流行已成为影响我国北方枣树养蜂业发展的主要因素之一。然而,蜜蜂枣花病的致病机制知之甚少。在这里,我们首先使用HE染色对中肠进行了形态学观察,发现受枣花疾病影响的蜜蜂表现出中肠损伤,并伴有营养膜脱离。发现枣花病会增加几丁质酶和羧酸酯酶(CarE)的活性,并降低超氧化物歧化酶(SOD)的活性,过氧化氢酶(CAT),谷胱甘肽S-转移酶(GST),和蜜蜂中肠中CYP450的含量。转录组数据确定了患病和健康蜜蜂中肠中的119个差异表达基因,包括CYP6a13、CYP6a17、CYP304a1、CYP6a14、AADC、和AGXT2,它们与氧化还原酶活性和维生素结合有关。总之,采集红枣花蜜可以降低蜜蜂中肠的抗氧化和解毒能力,在更严重的情况下,破坏肠道结构,表明肠道损伤可能是大枣花蜜导致蜜蜂死亡的主要原因。本研究为蜜蜂枣花病的发病机制提供了新的见解。
Honeybees are prone to poisoning, also known as jujube flower disease, after collecting nectar from jujube flowers, resulting in the tumultuous demise of foragers. The prevalence of jujube flower disease has become one of the main factors affecting the development of the jujube and beekeeping industries in Northern
China. However, the pathogenic mechanisms underlying jujube flower disease in honeybees are poorly understood. Herein, we first conducted morphological observations of the midgut using HE-staining and found that jujube flower disease-affected honeybees displayed midgut damage with peritrophic membrane detachment. Jujube flower disease was found to increase the activity of chitinase and
carboxylesterase (CarE) and decrease the activity of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and the content of CYP450 in the honeybee midgut. Transcriptomic data identified 119 differentially expressed genes in the midgut of diseased and healthy honeybees, including CYP6a13, CYP6a17, CYP304a1, CYP6a14, AADC, and AGXT2, which are associated with oxidoreductase activity and vitamin binding. In summary, collecting jujube flower nectar could reduce antioxidant and detoxification capacities of the honeybee midgut and, in more severe cases, damage the intestinal structure, suggesting that intestinal damage might be the main cause of honeybee death due to jujube nectar. This study provides new insights into the pathogenesis of jujube flower disease in honeybees.