In stem cells, pyruvate from glycolysis will mainly be metabolized to lactate as a result of an uncoupling of the citric acid cycle and the oxidative phosphorylation pathway (1,2), and by these means we hypothesize that hyperpolarised [1-13C] pyruvate can characterize the MSC viability and differentiation state. The primary source for harvesting Mesenchymal Stem cells (MSC) is the bone marrow, but MSC from adipose tissue have the same potential. This study aims to characterize the MSC´s harvested from adipose tissue and grown in culture for 3 weeks.MSCs were harvested from adipose tissue and grown in culture. After 3 weeks of standard culture conditions, the cells were characterized according to morphology, their ability to differentiate into osteocytes, and their specific expression of surface receptors. With regard to their metabolic profile, the cells were loaded to 3D Scaffolds and after 9 days of housing, 6 scaffolds with a total of 10 million cells were placed in a five mm bioreactor system in a horizontal 9.4 T MRI system (Agilent, UK). For hyperpolarisation experiments, [1-13C] pyruvate was polarised in a SpinLab (GE Healthcare, DK) and after injection of 5 mM pyruvate, 13C spectra were continuously acquired over 3 minutes with an interval of 1 second and the lactate-to-pyruvate ratio was calculated.Three weeks old adipose tissue-derived MSC demonstrated characteristic morphology (Figure 1A and B) as well as harboured the ability to differentiate into osteocytes (Figure 1C). The cells also expressed cell surface antigens specific for MSC such as CD90 (Figure 1D), CD73 (Figure 1E) and CD105 (Figure 1F) but not CD34, CD14, CD45, CD11b, CD19 and HLA-DR (Figure 1G and H). The lactate-to-pyruvate ratio was calculated using 5 mM hyperpolarised [1-13C] pyruvate and Figure 2A shows a representative diagram of the acquired data. A pronounced pyruvate-to-lactate ratio with a mean of 4.4 ± 0.7 % (Figure 2B) was found for the MSCs. This study demonstrates that MSCs harvested from adipose tissues and grown in culture for 3 weeks possess the characteristics previously found for bone marrow derived MSCs (3, 4).These cells have the ability to self-renew and differentiate and possess a high flux of glucose uptake and lactate production to generate sufficient energy. These data indicate clear-cut stem cell regulation to maintain a specific balance of self-renewal and differentiation.