In reserve mode?

A new study led by researchers at Dresden University of Technology (TUD) shows that cells in the brains of fruit flies have the remarkable ability to switch their energy production to fat. This switch acts as a trigger to send signals to other organs in the body to start delivering lipids from fat stores to the brain in times of hunger. The results were published in the journal Nature Communications.

The brain, one of the most energy-intensive organs in the human body, normally relies on sugar as its primary energy source. However, when undernourished, the brain can adapt and utilise alternative fuels such as ketone bodies from stored fat. The question of whether brain cells rely exclusively on externally derived fuel or whether they can utilise fat directly has long puzzled scientists.

Metabolic switch

Under the direction of Prof. Stefanie Schirmeier from the Faculty of Biology and Dr Marko Brankatschk from the Faculty of Biology, the project was launched. Under the direction of Prof. Stefanie Schirmeier from the Faculty of Biology and Dr. Marko Brankatschk from the Biotechnology Centre (BIOTEC) at TU Dresden, the research team has used a wide range of methods including genetic manipulation, molecular biology, lipid analysis and behavioural studies to show how fruit fly brain cells can switch to fat in order to produce alternative neuronal fuel and protect themselves from neurodegeneration.

„When we think of the brain, we often think of neurons, but there are other cell types in the brain called glial cells. They play an important role in supporting and maintaining neurons. Our study shows that these glial cells respond to sugar deprivation by activating fat utilisation. In the fruit fly, these cells utilise fats stored in lipid pools or absorb lipids from the bloodstream to produce ketones that can be consumed by neurons. This switching is crucial for the survival of the fly," explains Dr Marko Brankatschk, research group leader at BIOTEC.

Metabolic sensor

The study also revealed that the glial cells act as messengers that inform the body of the brain's energy shortage. „Our results suggest that the metabolic switch in the glial cells acts as a trigger and initiates a communication cascade that alerts the rest of the body to the difficult metabolic situation in the brain. The body's fat-storing organs then mobilise reserves to maintain the brain's energy supply. It remains to be seen whether there is a similar mechanism in the human brain," explains Prof. Schirmeier, emphasising:
„Our work is based on Drosophila melanogaster, the fruit fly that has long served as a valuable model organism for developmental and disease studies. Our study shows that it has the potential to provide insights into complex metabolic changes and their biological consequences“.

The Dresden University of Technology studies have the potential to expand our current understanding of brain metabolism and emphasise the importance of studying simple model organisms to uncover the precise mechanisms of complex biological processes.

&about the Biotechnology Centre (BIOTEC)
The Biotechnology Centre (BIOTEC) was founded in 2000 as a central scientific institution of TU Dresden with the aim of combining state-of-the-art research approaches in molecular and cell biology with the engineering sciences traditionally strong in Dresden. Since 2016, BIOTEC has been one of three institutes of the Centre for Molecular and Cellular Bioengineering (CMCB) at TU Dresden. BIOTEC occupies a central position in research and teaching in the field of molecular bioengineering and combines cell biological, biophysical and bioinformatic approaches. It thus makes a decisive contribution to the TU Dresden's profile in the fields of health sciences, biomedicine and bioengineering.
www.tud.de/biotec
www.tud.de/cmcb

&about the Faculty of Biology
When it was founded in 1994, the Faculty of Biology at TU Dresden became the nucleus of Dresden's life sciences, which today includes many other institutions in the DRESDEN-concept network. The research topics of the Faculty of Biology range from genetic and cell biology to physiological, developmental and biomimetic aspects as well as organismic and population biology. The disciplinary diversity of the research is also reflected in the three attractive study programmes, the Bachelor's programme „Molecular Biology and Biotechnology“ and the Master's programmes „Biology in Society“ and „Molecular Biosciences and Productive Biosystems“.

Scientific contacts:

Dr Marko Brankatschk
Tel: +49 351 463-40111
E-mail: marko.brankatschk@tu-dresden.de

Prof. Stefanie Schirmeier
Tel: +49 351 463-31922
E-mail: stefanie.schirmeier@tu-dresden.de

Original publication:

Ellen McMullen, Helen Hertenstein, Katrin Strassburger, Leon Deharde, Marko Brankatschk, Stefanie Schirmeier: Glycolytically impaired Drosophila glial cells fuel neural metabolism via β-oxidation. Nature Communications (May 2023)
Link: https://rdcu.be/dcTMN

Article from "innovationsreport" dated 28 June 2023