Biological characteristics of canine adipose-derived mesenchymal stem cells cultured in hypoxia / 中国组织工程研究

ABSTRACT

BACKGROUND: Previous studies have found that hypoxia has different effects on the proliferation and differentiation of mesenchymal stem cells and secretion of cytokines, but the effect of hypoxia on canine adipose-derived mesenchymal stem cells has not been seen. OBJECTIVE: To investigate the effect of hypoxic environment on the biological characteristics of canine adipose-derived mesenchymal stem cells. METHODS: Canine adipose-derived mesenchymal stem cells were isolated and cultured by enzyme digestion. Passage 2 adipose-derived mesenchymal stem cells could be divided into normoxia group (21% oxygen volume fraction) and hypoxia group (5% oxygen volume fraction). Morphological characteristics, proliferation speed, cell surface marker expression, differentiation capacity, and cytokine secretion level were compared between the two groups. RESULTS AND CONCLUSION: (1) The growth of adipose-derived mesenchymal stem cells cultured in hypoxic environment was good. The cell morphology was fusiform and polyhedral, the same as that of the normoxia group. (2) The proliferation rate of cells in the hypoxia group was accelerated, and the cell doubling time was shorter than that in the normoxia group (all P < 0.05). The differentiation time of lipogenesis and osteogenesis was shortened. (3) The expression of CD90, CD44 and CD105 was high in both normoxia group and hypoxia group, while the expression of CD45 was low. (4) The mRNA expression levels of brain-derived neurotrophic factor and vascular endothelial growth factor in the hypoxia group were 2.3 times (P < 0.05) and 3.0 times (P < 0.05) higher than those in the normoxia group. (5) The results indicated that the hypoxic environment had no significant effect on the morphology and surface marker of adipose-derived mesenchymal stem cells, but promoted cell proliferation, differentiation and cytokine secretion.