Department of Biochemistry and Molecular Medicine, College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia.
College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia.
Cells. 2024 Jun 12;13(12):1022. doi: 10.3390/cells13121022.
Mesenchymal stem cells (MSCs) of placental origin hold great promise in tissue engineering and regenerative medicine for diseases affecting cartilage and bone. However, their utility has been limited by their tendency to undergo premature senescence and phenotypic drift into adipocytes. This study aimed to explore the potential involvement of a specific subset of aging and antiaging genes by measuring their expression prior to and following in vitro-induced differentiation of placental MSCs into chondrocytes and osteoblasts as opposed to adipocytes. The targeted genes of interest included the various transcript variants (lamin A, lamin C, and lamin A∆10), sirtuin 7 (SIRT7), and SM22α, along with the classic aging markers plasminogen activator inhibitor 1 (PAI-1), p53, and p16. MSCs were isolated from the decidua basalis of human term placentas, expanded, and then analyzed for phenotypic properties by flow cytometry and evaluated for colony-forming efficiency. The cells were then induced to differentiate in vitro into chondrocytes, osteocytes, and adipocytes following established protocols. The mRNA expression of the targeted genes was measured by RT-qPCR in the undifferentiated cells and those fully differentiated into the three cellular lineages. Compared to undifferentiated cells, the differentiated chondrocytes demonstrated decreased expression of SIRT7, along with decreased PAI-1, lamin A, and SM22α expression, but the expression of p16 and p53 increased, suggesting their tendency to undergo premature senescence. Interestingly, the cells maintained the expression of lamin C, which indicates that it is the primary lamin variant influencing the mechanoelastic properties of the differentiated cells. Notably, the expression of all targeted genes did not differ from the undifferentiated cells following osteogenic differentiation. On the other hand, the differentiation of the cells into adipocytes was associated with decreased expression of lamin A and PAI-1. The distinct patterns of expression of aging and antiaging genes following in vitro-induced differentiation of MSCs into chondrocytes, osteocytes, and adipocytes potentially reflect specific roles for these genes during and following differentiation in the fully functional cells. Understanding these roles and the network of signaling molecules involved can open opportunities to improve the handling and utility of MSCs as cellular precursors for the treatment of cartilage and bone diseases.
胎盘来源的间充质干细胞（MSCs）在组织工程和再生医学中具有很大的潜力，可以治疗影响软骨和骨骼的疾病。然而，它们的应用受到其倾向于过早衰老和向脂肪细胞表型漂移的限制。本研究旨在通过测量胎盘 MSC 在体外向软骨细胞和成骨细胞分化之前和之后的特定衰老和抗衰老基因的表达，来探讨其潜在的作用。感兴趣的目标基因包括各种转录变体（核纤层蛋白 A、核纤层蛋白 C 和核纤层蛋白 AΔ10）、SIRT7 和 SM22α，以及经典的衰老标志物纤溶酶原激活物抑制剂 1（PAI-1）、p53 和 p16。从足月胎盘的底蜕膜中分离出 MSC，进行扩增，然后通过流式细胞术分析其表型特性，并评估集落形成效率。然后，根据既定方案在体外诱导细胞向软骨细胞、成骨细胞和脂肪细胞分化。通过 RT-qPCR 测量未分化细胞和完全分化为三种细胞谱系的细胞中目标基因的 mRNA 表达。与未分化细胞相比，分化的软骨细胞表现出 SIRT7 表达降低，同时 PAI-1、核纤层蛋白 A 和 SM22α 表达降低，但 p16 和 p53 表达增加，表明其有过早衰老的趋势。有趣的是，细胞保持核纤层蛋白 C 的表达，这表明它是影响分化细胞的机械弹性特性的主要核纤层变体。值得注意的是，细胞向成骨细胞分化后，所有目标基因的表达与未分化细胞没有差异。另一方面，细胞向脂肪细胞分化与核纤层蛋白 A 和 PAI-1 表达降低有关。MSC 体外诱导分化为软骨细胞、成骨细胞和脂肪细胞后，衰老和抗衰老基因的表达模式不同，这可能反映了这些基因在完全功能细胞分化过程中和之后的特定作用。了解这些作用和涉及的信号分子网络可以为改善 MSC 作为软骨和骨骼疾病治疗的细胞前体的处理和应用提供机会。
