Nagy 2014 Abstract MiP2014
|Investigation of the energy metabolism of microglial cells.|
Microglial cells play a key role in the pathomechanism of neurodegenerative disorders. These cells can enter metabolically different compartments in the CNS. We investigated, which of the compounds available in the extracellular space can serve as metabolic fuels for these cells.
Cellular oxygen consumption was measured with the Oroboros Oxygraph-2k, and extracellular acidification rate (ECAR) was measured on primary microglia and on the BV-2 microglial cell-line with the Seahorse Extracellular Flux Analyzer. ECAR was considered a parameter of glycolytic activity. Cells were incubated in Artificial Cerebrospinal Fluid (ACSF) supplemented with substrates available to the cells in the CSF: glutamine, glucose, lactate, keton bodies or pyruvate. ATP and ADP levels were measured using a luciferin/luciferase bioluminescent method. Viability was detected with annexin/calcein fluorescent staining and MTT spectrophotometric assay.
All of the substrates applied supported the metabolism of the cells and none of them influenced their viability negatively. In the presence of glutamine and pyruvate ROUTINE respiration was increased; furthermore, glutamine increased the scope of uncoupler-stimulated respiration above ROUTINE activity levels of the cells. However, in the presence of glucose, the respiration was decreased and the ECAR raised, indicating that glucose, added to microglial cells, stimulated glycolysis but inhibited oxidative metabolism (Crabtree effect). Addition of a lactate dehydrogenase inhibitor after glucose reversed this effect. In the presence of glucose, adding a mitochondrial fatty acid transporter inhibitor further increased the ECAR.
We conclude that microglial cells show high metabolic plasticity and use a wide range of substrates. Interpreting the ECAR results, we claim that these cells show high glycolytic capacity. Furthermore, we found that, besides glucose, glutamine was the most preferred substrate for microglial cells.
Supported by OTKA (NK 81983), TAMOP (4.2.2./B-09/1), MTA (MTA TKI 2013), Hungarian Brain Research Program (KTIA_13_NAP-A-III/6).
• O2k-Network Lab: HU Budapest Tretter L
Labels: MiParea: Respiration
Organism: Human Tissue;cell: Nervous system Preparation: Intact cells
Regulation: Substrate, Fatty acid Coupling state: ROUTINE, ET
HRR: Oxygraph-2k Event: C1, Poster MiP2014
1-Dep Medical Biochem MTA-SE, Lab Neurobiochem, Semmelweis Univ, 2-Inst Experim Medicine Hungarian Acad Sc; Budapest, Hungary. - [email protected]