Extracellular Flux Enables Real-time, Non-invasive Measurements of Cellular Metabolism

Metabolic changes in cells are very sensitive, early indicators of processes such as proliferation, differentiation, activation, and apoptosis. Seahorse Bioscience has developed an in vitro real time, bioenergetic assay for pathway determination and quantification. The XF24 Extracellular Flux Analyzer simultaneously measures cellular oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) of cells in 24 well microplates in minutes. OCR and ECAR can be used to profile both metabolic rate and the relative contributions of aerobic and anaerobic respiration. Extracellular Flux (XF) assays do not disturb cells and can therefore be repeated frequently to acquire time resolved data, or to compare basal and drug-stimulated metabolic rates. XF24 assays of two cancer cell lines demonstrated an increased dependency on glycolysis that can be modulated with Topotecan. XF24 assays of C2C12 myotubes demonstrated a rapid and dramatic increase in OCR, indicative of Fatty Acid Oxidation, following the addition of Palmitate. The response was inhibited by the CPT-1 inhibitor Etomoxir.