Comparison of proliferation and differentiation capacity of human adipocyte precursor cells from the omental and subcutaneous adipose tissue depot of obese subjects

Upper body obesity is characterized by an expansion of visceral adipose tissue and associated with an increased susceptibility for diabetes and cardiovascular disease. To get a better understanding of the regulation of body fat distribution, adipocyte development was compared between the omental and subcutaneous adipose tissue region in 29 obese subjects. Therefore, the proliferation and differentiation capacity in primary cultures of adipose tissue-derived stromal cells were studied. Differentiation of preadipocytes was assessed by morphological criteria and determination of glycerol-3-phosphate dehydrogenase after stimulation by standardized adipogenic conditions. Proliferation was stimulated using fetal calf serum and assessed by counting the cell number in the culture dishes. Stromal cells of the subcutaneous region proliferated faster than those of the omental region, whereas there was no regional difference in adipose differentiation with any of the adipogenic media. There were more endothelial cells in the cultures from the omental than from the subcutaneous tissue, but there was no correlation between endothelial cell contamination and proliferation capacity, suggesting that the regional difference in proliferation capacity was not due to regional differences in the amount of endothelial cells. There was a negative correlation between donor age and proliferation of subcutaneous cells but not of omental cells, possibly explaining the greater capacity for adipose tissue growth in the omental as compared to the subcutaneous depot with aging. In conclusion, there may exist regional differences in adipose tissue growth with regard to proliferation capacity, whereas there are apparently no differences in differentiation capacity between subcutaneous and omental preadipocytes.