Metabolic Enzymes in Glial Cells of the Honeybee Brain and Their Associations with Aging, Starvation and Food Response, 2017

The honey bee has been extensively studied as a model for neuronal circuit and memory function and more recently has emerged as an unconventional model in biogerontology. Yet, the detailed knowledge of neuronal processing in the honey bee brain contrasts with the very sparse information available on glial cells. In other systems glial cells are involved in nutritional homeostasis, detoxification, and aging. These glial functions have been linked to metabolic enzymes, such as glutamine synthetase and glycogen phosphorylase. As a step in identifying functional roles and potential differences among honey bee glial types, this project examined the spatial distribution of these enzymes and asked if enzyme abundance is associated with aging and other processes essential for survival. Using immunohistochemistry and confocal laser microscopy we demonstrate that glutamine synthetase and glycogen phosphorylase are abundant in glia but appear to co-localize with different glial sub-types. The overall spatial distribution of both enzymes was not homogenous and differed markedly between different neuropiles and also within each neuropil. Using semi-quantitative Western blotting it was found that rapid aging, typically observed in shortest-lived worker bees (foragers), was associated with declining enzyme levels. Further, enzyme abundance changes after severe starvation stress, and glutamine synthetase is associated with food response. Together, the data indicate that aging and nutritional physiology in bees are linked to glial specific metabolic enzymes. Enzyme specific localization patterns suggest a functional differentiation among identified glial types.

The data material consists of four files. The spreadsheat data allows to identify for each blot and lane the experiment/treatment.
- Experiment Starvation with ST=starved and SA=satiated for Fig. 4
- Experiment gustatory responsiveness/GRS with L=low and H=high responders for Fig. 5
- Experiment Aging with OF=old and YF=young foragers for Fig. 6

Data are freely available for downloading.