Effects of glutamine, glucose, and oxygen concentration on the metabolism and proliferation of rabbit adipose-derived stem cells

The use of adipose-derived stem cells (ASCs) for tissue engineering involves exposing them to metabolically adverse conditions. This study examined the metabolism, proliferation, and viability of ASCs under various oxygen, glucose, and glutamine concentrations to determine how these cells respond to such environments. ASCs were cultured in each of 8 media preparations containing 4.8 or 21.5 mM glucose, and 0, 2, 4, or 6 mM glutamine. The ASCs were cultured under normoxic (20% O₂) and hypoxic (0.1% O₂) conditions. Conditioned media were collected and assayed for glucose, glutamine, lactate, pyruvate, and glutamate. Cell proliferation and cell death were measured after 5 days of culture. ASCs remained metabolically active under all culture conditions; however, their proliferation rate was significantly reduced in the absence of glutamine. Hypoxia resulted in increased cell death. ASCs are a viable source of stem cells for tissue engineering purposes, although substantial challenges remain. These cells are able to survive in environments with limited oxygen and glutamine and thus may be able to survive brief periods of limited nutrient transport after implantation.