Pre-culturing human adipose tissue mesenchymal stem cells under hypoxia increases their adipogenic and osteogenic differentiation potentials

Objectives: Hypoxia is an important factor in many aspects of stem- cell biology including their viability, proliferation, differentiation and migration. We evaluated whether low oxygen level ( 2%) affected human adipose tissue mesenchymal stem- cell ( hAT- MSC) phenotype, population growth, viability, apoptosis, necrosis and their adipogenic and osteogenic differentiation potential. Materials and methods: hAT- MSCs from four human donors were cultured in growth medium under either normoxic or hypoxic conditions for 7 days and were then transferred to normoxic conditions to study their differentiation potential. Results: Hypoxia enhanced hAT- MSC expansion and viability, whereas expression of mesenchymal markers such as CD90, CD73 and endothelial progenitor cell marker CD34, remained unchanged. We also found that pre- culturing hAT- MSCs under hypoxia resulted in their enhanced ability to differentiate into adipocytes and osteocytes. Conclusions: This protocol could be useful for maximizing hAT- MSC potential to differentiate in vitro into the adipogenic and osteogenic lineages, for use in plastic and reconstructive surgery, and in tissue engineering strategies.