Institute of Entomology, Biology Centre, CAS, Branišovská 31, 370 05 České Budějovice, Czech Republic; Faculty of Science, University of South Bohemia, Branišovská 31, 370 05 České Budějovice, Czech Republic.
Institute of Soil Biology, Biology Centre, CAS, Na Sádkách 7, 370 05 České Budějovice, Czech Republic.
Comp Biochem Physiol A Mol Integr Physiol. 2022 Feb;264:111115. doi: 10.1016/j.cbpa.2021.111115. Epub 2021 Nov 12.
Worker honey bees are subject to biochemical and physiological changes throughout the year. This study aimed to provide the reasons behind these fluctuations. The markers analysed included lipid, carbohydrate, and protein levels in the haemolymph; the activity of digestive enzymes in the midgut; the levels of adipokinetic hormone (AKH) in the bee central nervous system; the levels of vitellogenins in the bee venom and haemolymph; and the levels of melittin in the venom. The levels of all the main nutrients in the haemolymph peaked mostly within the period of maximal bee activity, whereas the activity of digestive enzymes mostly showed a two-peak course. Furthermore, the levels of AKHs fluctuated throughout the year, with modest but significant variations. These data suggest that the role of AKHs in bee energy metabolism is somewhat limited, and that bees rely more on available food and less on body deposits. Interestingly, the non-metabolic characteristics also fluctuated over the year. The vitellogenin peak reached its maximum in the haemolymph in winter, which is probably associated with the immunoprotection of long-lived winter bees. The analysis of bee venom showed the maximal levels of vitellogenin in autumn; however, it is not entirely clear why this is the case. Finally, melittin levels showed strong fluctuations, suggesting that seasonal control was unlikely.
工蜂在一年中会经历生化和生理变化。本研究旨在探讨这些波动的原因。分析的标志物包括血淋巴中的脂质、碳水化合物和蛋白质水平；中肠消化酶的活性；蜜蜂中枢神经系统中的促前胸腺激素 (AKH) 水平；蜜蜂毒液和血淋巴中的卵黄蛋白原水平；以及毒液中的蜂毒素水平。血淋巴中所有主要营养素的水平大多在蜜蜂活动的高峰期达到峰值，而消化酶的活性大多呈双峰曲线。此外，AKH 的水平全年波动，变化虽小但有意义。这些数据表明，AKH 在蜜蜂能量代谢中的作用有些有限，蜜蜂更多地依赖现有食物，而不是依赖体内储存。有趣的是，非代谢特性也随年份而波动。卵黄蛋白原在冬季血淋巴中的峰值最高，这可能与长寿冬季蜜蜂的免疫保护有关。毒液分析显示卵黄蛋白原在秋季达到最高水平；然而，为什么会这样还不完全清楚。最后，蜂毒素水平波动剧烈，表明季节性控制不太可能。
