Aubin Kim, Safoine Meryem, Proulx Maryse, Audet-Casgrain Marie-Alice, Côté Jean-François, Têtu Félix-André, Roy Alphonse, Fradette Julie
Centre de recherche en organogénèse expérimentale de l'Université Laval / LOEX, Québec, Canada; Division of Regenerative Medicine, CHU de Québec Research Centre, Québec, Canada.
Centre de recherche en organogénèse expérimentale de l'Université Laval / LOEX, Québec, Canada.
PLoS One. 2015 Sep 14;10(9):e0137612. doi: 10.1371/journal.pone.0137612. eCollection 2015.
Representative modelling of human adipose tissue functions is central to metabolic research. Tridimensional models able to recreate human adipogenesis in a physiological tissue-like context in vitro are still scarce. We describe the engineering of white adipose tissues reconstructed from their cultured adipose-derived stromal precursor cells. We hypothesize that these reconstructed tissues can recapitulate key functions of AT under basal and pro-inflammatory conditions. These tissues, featuring human adipocytes surrounded by stroma, were stable and metabolically active in long-term cultures (at least 11 weeks). Secretion of major adipokines and growth factors by the reconstructed tissues was determined and compared to media conditioned by human native fat explants. Interestingly, the secretory profiles of the reconstructed adipose tissues indicated an abundant production of leptin, PAI-1 and angiopoietin-1 proteins, while higher HGF levels were detected for the human fat explants. We next demonstrated the responsiveness of the tissues to the pro-inflammatory stimulus TNF-α, as reflected by modulation of MCP-1, NGF and HGF secretion, while VEGF and leptin protein expression did not vary. TNF-α exposure induced changes in gene expression for adipocyte metabolism-associated mRNAs such as SLC2A4, FASN and LIPE, as well as for genes implicated in NF-κB activation. Finally, this model was customized to feature adipocytes representative of progressive stages of differentiation, thereby allowing investigations using newly differentiated or more mature adipocytes. In conclusion, we produced tridimensional tissues engineered in vitro that are able to recapitulate key characteristics of subcutaneous white adipose tissue. These tissues are produced from human cells and their neo-synthesized matrix elements without exogenous or synthetic biomaterials. Therefore, they represent unique tools to investigate the effects of pharmacologically active products on human stromal cells, extracellular matrix and differentiated adipocytes, in addition to compounds modulating adipogenesis from precursor cells.
人类脂肪组织功能的代表性模型是代谢研究的核心。能够在体外类似生理组织的环境中重现人类脂肪生成的三维模型仍然很少。我们描述了从培养的脂肪来源的基质前体细胞重建白色脂肪组织的工程方法。我们假设这些重建组织可以概括基础和促炎条件下脂肪组织的关键功能。这些组织以被基质包围的人类脂肪细胞为特征，在长期培养（至少11周）中稳定且代谢活跃。测定了重建组织中主要脂肪因子和生长因子的分泌，并与人类天然脂肪外植体条件培养基进行了比较。有趣的是，重建脂肪组织的分泌谱表明瘦素、PAI-1和血管生成素-1蛋白大量产生，而人类脂肪外植体中检测到更高的HGF水平。接下来，我们证明了组织对促炎刺激TNF-α的反应性，这通过MCP-1、NGF和HGF分泌的调节得以体现，而VEGF和瘦素蛋白表达没有变化。TNF-α暴露诱导了脂肪细胞代谢相关mRNA（如SLC2A4、FASN和LIPE）以及与NF-κB激活相关基因的表达变化。最后，该模型经过定制，以具有代表分化不同阶段的脂肪细胞为特征，从而允许使用新分化或更成熟的脂肪细胞进行研究。总之，我们生产了体外工程化的三维组织，能够概括皮下白色脂肪组织的关键特征。这些组织由人类细胞及其新合成的基质成分产生，无需外源性或合成生物材料。因此，它们是研究药理活性产品对人类基质细胞、细胞外基质和分化脂肪细胞的影响以及调节前体细胞脂肪生成的化合物的独特工具。
