Original paper
Light-induced disruptions elevate norepinephrine and impair cognition in honey bees
Gu, Gaoying; Wang, Ziqi; Li, Jianjun; Dong, Shihao; Nieh, James C.; Tan, Ken
Entomologia Generalis Volume 45 Number 2 (2025), p. 527 - 536
published: May 22, 2025
published online: Apr 14, 2025
manuscript accepted: Feb 3, 2025
manuscript revision received: Dec 13, 2024
manuscript revision requested: Nov 27, 2024
manuscript received: Aug 5, 2024
DOI: 10.1127/entomologia/2025/2917
Open Access (paper may be downloaded free of charge)
Abstract
Light exposure is a primary cue that shapes circadian rhythms in many organisms, yet the harmful effects of artificial lighting are becoming increasingly apparent. We examined the impact of low-intensity illumination (2.3 µmol/s/m²) on young honey bees (Apis mellifera) and found that continuous light significantly increased mortality and impaired olfactory learning and memory. Although norepinephrine (NE) levels peaked at midnight under all conditions – normal light/dark, continuous darkness, and continuous light – bees exposed to constant light had consistently higher NE concentrations. Elevating NE levels in bees maintained under a normal light cycle produced similar deficits in survival and cognition, reinforcing the link between NE and light-induced stress. These results provide the first evidence that NE, like octopamine, contributes to stress responses and cognitive impairment in bees and underscore the importance of understanding how altered lighting environments influence insect physiology and behavior.
Keywords
Circadian rhythms •
artificial illumination •
olfactory learning •
foraging efficiency •
biogenic amines •
Apis mellifera