1 H NMR Profiling of Honey Bee Brains across Varying Ages and Seasons.

Simple Summary: Metabolic changes in adult honey bee brains associated with the seasons and aging in honey bees (Apis mellifera) were assessed using nuclear magnetic resonance (NMR) spectroscopy. Brains were dissected from newly emerged, 14-day– old, and 28-day– old bees that were collected over the summer, as well as brood nest bees collected in the fall, winter, and spring. Changes in the brain metabolome indicated that worker bees undergo adaptations throughout their lives, with notable shifts occurring between newly emerged and older individuals. Furthermore, the seasons affected the honey bee brain metabolome, highlighting differences in metabolic responses to changes in the environment and resource availability. While previous studies have reported differences in the metabolome of whole bodies between summer and winter bees, or in the brains of forager bees infected with a virus, the present study has revealed the metabolome of the honey bee brain as it ages. Several potential markers were identified for assessing aging of the bee brain, such as the potential neurotransmitter β-alanine and neurotransmitter-precursors/intermediates, phenylalanine, tyrosine, tryptophan, and O-phosphocholine. Honey bees (Apis mellifera) provide a useful model for studying aging because of the differences in longevity between the relatively short-lived summer and long-lived winter bees, as well as bees lacking signs of cognitive senescence as they age. Bee brains were dissected from newly emerged, 14-day–, and 28-day– old bees in mid- and late summer, as well as brood nest bees in fall, winter, and spring, before, during, and after overwintering, respectively. Brains were examined with nuclear magnetic resonance (NMR) spectroscopy to analyze their metabolome. Nine variable importance in projection (VIP) variables were identified, primarily amino acids and choline derivatives. Differences in metabolite concentrations were found with different ages of summer bees, mostly between newly emerged and 14-day– old bees, such as a decrease in phenylalanine and an increase in β-alanine, but there were also changes in older adults, such as o-phosphocholine that declined in 28-day– old bees. Differences in brood nest bees were observed, including a decline in tryptophan and an increase in β-alanine. These may provide distinct metabolomic signatures with age and season. Such research holds promise for a better understanding of the complex interplays between bee physiology, development, and aging, which has implications for improving bee health and management. [ABSTRACT FROM AUTHOR]