A fluorescent probe for labeling mitochondria helps scientists study fat-burning brown adipose tissue
A new cellular labeling strategy gives researchers an efficient tool for studying the development of tissue that could help prevent the onset of obesity and cardiovascular disease .
Most people think about fat in terms of the white adipose tissue that stores the body’s excess energy, and which steadily — and visibly — accumulates as one becomes out of shape or obese. However, there is another type of fat tissue that can prevent rather than promote weight gain.
“Brown adipose tissue not only stores fats, but also has the ability to burn fats to release energy as heat,” explains Bin Liu of the A*STAR Institute of Materials Research and Engineering.
Liu sees this tissue as a promising target for anti-obesity drugs, and her group set about designing a fluorescent molecule that could help scientists visualize the development of brown adipose cells. These cells can be characterized based on the number and organization of their mitochondria, the organelles that drive cellular metabolism.
However, existing mitochondrial dyes tend to absorb each other’s fluorescence at high concentrations, resulting in a weaker overall signal as they accumulate.
In collaboration with Hong Kong University of Science and Technology researcher Ben Zhong Tang, Liu’s team devised a fluorescent dye that exhibits ‘aggregation-induced emission’. “This means that the probe does not emit fluorescence in dilute solutions,” explains Liu, “but it becomes highly fluorescent when it accumulates in mitochondria, without any self-quenching effects.”
After 20 minutes of treatment with their AIE-MitoGreen-1 probe, Liu’s group achieved bright labeling of mitochondria in brown adipose cells that lasted for more than a day. This labeling approach also left cultured cells largely unharmed, whereas only 10 per cent of cells survived prolonged treatment with a commercially available mitochondrial dye. The researchers subsequently used AIE-MitoGreen-1 to monitor the development of brown adipose tissue from precursor cells, observing changes in cell shape and mitochondrial organization over seven days (see image).
Since the basic stages of brown adipose development are well characterized, this probe could help identify treatments that stimulate or impede this process. “We hope to use our probe to monitor the activity of brown adipose cells in response to various stimuli, such as drug intervention or temperature changes,” says Liu. Her group aims to further improve their probe so that it shines longer and brighter. Ultimately, she hopes to develop variants that fluoresce at near-infrared wavelengths, which can be detected deeper within living tissue. “We would apply these probes to long-term monitoring of brown adipose cells in animal models.”
 Gao, M., Sim, C. K., Leung, C. W. T., Hu, Q., Feng, G. et al. A fluorescent light-up probe with AIE characteristics for specific mitochondrial imaging to identify differentiating brown adipose cells. Chemical Communications 50, 8312–8315 (2014).
A*STAR Research | ResearchSEA
How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH
A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
23.06.2017 | Physics and Astronomy
23.06.2017 | Physics and Astronomy
23.06.2017 | Information Technology