Gatie Mohamed I, Kelly Gregory M
1Department of Biology, Collaborative Graduate Specialization in Developmental Biology, The University of Western Ontario, London, ON Canada.
2Department of Paediatrics, The University of Western Ontario, London, ON Canada.
Cell Death Discov. 2018 Sep 26;4:42. doi: 10.1038/s41420-018-0102-1. eCollection 2018.
Glucose metabolism has a crucial role for providing substrates required to generate ATP and regulate the epigenetic landscape. We reported that F9 embryonal carcinoma stem-like cells require cytosolic reactive oxygen species to differentiate into extraembryonic endoderm; however, mitochondrial sources were not examined. To extend these studies, we examined the metabolic profile of early and late-passage F9 cells, and show that their ability to differentiate is similar, even though each population has dramatically different metabolic profiles. Differentiated early-passage cells relied on glycolysis, while differentiated late-passage cells transitioned towards oxidative phosphorylation (OXPHOS). Unexpectedly, electron transport chain protein stoichiometry was disrupted in differentiated late-passage cells, whereas genes encoding mitofusion 1 and 2, which promote mitochondrial fusion and favor OXPHOS, were upregulated in differentiated early-passage cells. Despite this, early-passage cells cultured under conditions to promote glycolysis showed enhanced differentiation, whereas promoting OXPHOS in late-passage cells showed a similar trend. Further analysis revealed that the distinct metabolic profiles seen between the two populations is largely associated with changes in genomic integrity, linking metabolism to passage number. Together, these results indicate that passaging has no effect on the potential for F9 cells to differentiate into extraembryonic endoderm; however, it does impact their metabolic profile. Thus, it is imperative to determine the molecular and metabolic status of a stem cell population before considering its utility as a therapeutic tool for regenerative medicine.
葡萄糖代谢在提供生成三磷酸腺苷（ATP）所需的底物以及调节表观遗传格局方面起着至关重要的作用。我们曾报道，F9胚胎癌细胞样干细胞需要胞质活性氧来分化为胚外内胚层；然而，线粒体来源并未进行研究。为了拓展这些研究，我们检测了早代和晚代F9细胞的代谢谱，并发现尽管每个群体的代谢谱差异显著，但它们的分化能力相似。分化的早代细胞依赖糖酵解，而分化的晚代细胞则向氧化磷酸化（OXPHOS）转变。出乎意料的是，分化的晚代细胞中电子传递链蛋白化学计量被破坏，而在分化的早代细胞中，促进线粒体融合并有利于OXPHOS的编码线粒体融合蛋白1和2的基因上调。尽管如此，在促进糖酵解的条件下培养的早代细胞显示出增强的分化，而在晚代细胞中促进OXPHOS也呈现出类似趋势。进一步分析表明，两个群体之间观察到的不同代谢谱在很大程度上与基因组完整性的变化相关，将代谢与传代次数联系起来。总之，这些结果表明传代对F9细胞分化为胚外内胚层的潜力没有影响；然而，它确实会影响它们的代谢谱。因此，在考虑将干细胞群体用作再生医学的治疗工具之前，确定其分子和代谢状态至关重要。
