Guangxi Engineering Center in Biomedical Material for Tissue and Organ Regeneration, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China.
Guangxi Collaborative Innovation Center for Biomedicine, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, China.
J Orthop Surg Res. 2020 Sep 23;15(1):437. doi: 10.1186/s13018-020-01965-3.
The differentiation of bone mesenchymal stem cells (BMSCs) into adipogenesis (AD) rather than osteogenesis (OS) is an important pathological feature of osteoporosis. Illuminating the detailed mechanisms of the differentiation of BMSCs into OS and AD would contribute to the interpretation of osteoporosis pathology.
To identify the regulated mechanism in lineage commitment of the BMSCs into OS and AD in the early stages, the gene expression profiles with temporal series were downloaded to reveal the distinct fates when BMSCs adopt a committed lineage. For both OS and AD lineages, the profiles of days 2-4 were compared with day 0 to screen the differentially expressed genes (DEGs), respectively. Next, the functional enrichment analysis was utilized to find out the biological function, and protein-protein interaction network to predict the central genes. Finally, experiments were performed to verify our finding.
FoxO signaling pathway with central genes like FoxO3, IL6, and CAT is the crucial mechanism of OS, while Rap1 signaling pathway of VEGFA and FGF2 enrichment is more significant for AD. Besides, PI3K-Akt signaling pathway might serve as the latent mechanism about the initiation of differentiation of BMSCs into multiple lineages.
Above hub genes and early-responder signaling pathways control osteogenic and adipogenic fates of BMSCs, which maybe mechanistic models clarifying the changes of bone metabolism in the clinical progress of osteoporosis. The findings provide a crucial reference for the prevention and therapy of osteoporosis.
骨间充质干细胞(BMSCs)向脂肪生成(AD)而非成骨(OS)的分化是骨质疏松症的一个重要病理特征。阐明 BMSCs 向 OS 和 AD 分化的详细机制将有助于解释骨质疏松症的病理。
为了确定 BMSCs 向 OS 和 AD 早期谱系分化的调控机制,下载了具有时间序列的基因表达谱,以揭示 BMSCs 采用特定谱系时的不同命运。对于 OS 和 AD 谱系,分别将第 2-4 天的图谱与第 0 天进行比较,以筛选差异表达基因(DEGs)。接下来,利用功能富集分析来寻找生物功能,利用蛋白质-蛋白质相互作用网络来预测核心基因。最后,进行实验来验证我们的发现。
FoxO 信号通路,其核心基因如 FoxO3、IL6 和 CAT,是 OS 的关键机制,而 VEGFA 和 FGF2 富集的 Rap1 信号通路对 AD 更为重要。此外,PI3K-Akt 信号通路可能是 BMSCs 向多个谱系分化的潜在机制。
上述核心基因和早期反应信号通路控制着 BMSCs 的成骨和成脂命运,这些可能是阐明骨质疏松症临床进展中骨代谢变化的机制模型。这些发现为骨质疏松症的预防和治疗提供了重要参考。