Diverse Effects of Cyclic AMP Variants on Osteogenic and Adipogenic Differentiation of Human Mesenchymal Stromal Cells
Diverse Effects of Cyclic AMP Variants on Osteogenic and Adipogenic Differentiation of Human Mesenchymal Stromal Cells
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DOI：
10.1089/ten.tea.2011.0484
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发表时间：
2012-07-01
影响因子：
4.1
通讯作者：
de Boer, Jan
中科院分区：
文献类型：
--
作者：
Doorn, Joyce;Leusink, Maarten;de Boer, Jan
人间充质基质细胞（hMSCs）的成骨分化可能用于基于细胞的骨组织工程应用，以提高这些细胞的骨形成潜力。成骨分化和成脂分化被认为是相互排斥的，尽管已经分别鉴定了诱导成骨或成脂分化的几种信号传导途径和信号，但是关于如何最佳地将hMSCs分化成骨谱系还没有普遍共识。一些途径也被报道参与成脂和成骨分化，例如，蛋白激酶A（PKA）途径，本研究的目的是更详细地研究cAMP/PKA信号传导在hMSCs分化中的作用。我们发现，激活这一途径与二丁酰-cAMP的结果增强碱性磷酸酶的表达，而另一个cAMP类似物诱导脂肪形成在长期矿化培养。由8-溴-cAMP诱导的成脂分化伴随有更强的PKA活性和更高的cAMP应答基因表达，表明更强的活化与成脂分化相关。此外，全基因组表达分析显示，在8-br-cAMP处理的细胞中脂肪形成基因的表达增加。此外，通过定量聚合酶链反应，我们显示过氧化物酶体增殖物激活受体-γ激活的差异，无论是单独或与地塞米松结合，从而证明PKA途径的差异效应，最有可能取决于其激活模式。
Osteogenic differentiation of human mesenchymal stromal cells (hMSCs) may potentially be used in cell-based bone tissue-engineering applications to enhance the bone-forming potential of these cells. Osteogenic differentiation and adipogenic differentiation are thought to be mutually exclusive, and although several signaling pathways and cues that induce osteogenic or adipogenic differentiation, respectively, have been identified, there is no general consensus on how to optimally differentiate hMSCs into the osteogenic lineage. Some pathways have also been reported to be involved in both adipogenic and osteogenic differentiation, as for example, the protein kinase A (PKA) pathway, and the aim of this study was to investigate the role of cAMP/PKA signaling in differentiation of hMSCs in more detail. We show that activation of this pathway with dibutyryl-cAMP results in enhanced alkaline phosphatase expression, whereas another cAMP analog induces adipogenesis in long-term mineralization cultures. Adipogenic differentiation, induced by 8-bromo-cAMP, was accompanied by stronger PKA activity and higher expression of cAMP-responsive genes, suggesting that stronger activation correlates with adipogenic differentiation. In addition, a whole-genome expression analysis showed an increase in expression of adipogenic genes in 8-br-cAMP-treated cells. Furthermore, by means of quantitative polymerase chain reaction, we show differences in peroxisome proliferator-activated receptor-gamma activation, either alone or in combination with dexamethasone, thus demonstrating differential effects of the PKA pathway, most likely depending on its mode of activation.