低氧培养犬脂肪间充质干细胞的生物学特性

Biological characteristics of canine adipose-derived mesenchymal stem cells cultured in hypoxia

背景:以往研究发现低氧对间充质干细胞增殖、分化及细胞因子分泌等方面均有不同程度的影响,但低氧对犬脂肪间充质干细胞的影响尚未见相关研究。目的:探讨低氧环境对犬脂肪间充质干细胞生物学特性的影响。方法:通过酶消化法分离培养犬脂肪间充质干细胞,第2代时分为常氧组(氧气体积分数为21%)和低氧组(氧气体积分数为5%),比较了两组细胞的形态特征、增殖速度、细胞表面标志物、分化能力和细胞因子分泌水平等。结果与结论:①低氧环境下培养的脂肪间充质干细胞生长状况良好,细胞形态与常氧组一样,均呈梭形和多棱形;②低氧组的细胞增殖速度加快,细胞倍增时间比常氧组短(P均<0.05),成脂、成骨分化出现时间较早;③常氧组和低氧组脂肪间充质干细胞均高表达CD90、CD44和CD105,低表达CD45;④低氧组脂肪间充质干细胞的脑源性神经营养因子和血管内皮生长因子mRNA表达量分别是常氧组的2.3倍(P<0.05)和3.0倍(P<0.05);⑤结果提示低氧环境对脂肪间充质干细胞的形态、表面标记物无明显影响,但对细胞增殖、分化和细胞因子分泌能力有促进作用。

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 brainderived 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.