Xu He N, Addis Russell C, Goings Davida F, Nioka Shoko, Chance Britton, Gearhart John D, Li Lin Z
Molecular Imaging Laboratory, Department of Radiology University of Pennsylvania, School of Medicine Philadelphia, PA 19104, USA.
Britton Chance Laboratory of Redox Imaging Johnson Research Foundation Department of Biochemistry and Biophysics University of Pennsylvania, School of Medicine Philadelphia, PA 19104, USA.
J Innov Opt Health Sci. 2011 Jul;4(3):279-288. doi: 10.1142/s1793545811001617.
Redox state mediates embryonic stem cell (ESC) differentiation and thus offers an important complementary approach to understanding the pluripotency of stem cells. NADH redox ratio (NADH/(Fp + NADH)), where NADH is the reduced form of nicotinamide adenine dinucleotide and Fp is the oxidized flavoproteins, has been established as a sensitive indicator of mitochondrial redox state. In this paper, we report our redox imaging data on the mitochondrial redox state of mouse ESC (mESC) colonies and the implications thereof. The low-temperature NADH/Fp redox scanner was employed to image mESC colonies grown on a feeder layer of gamma-irradiated mouse embryonic fibroblasts (MEFs) on glass cover slips. The result showed significant heterogeneity in the mitochondrial redox state within individual mESC colonies (size: ∼200-440 m), exhibiting a core with a more reduced state than the periphery. This more reduced state positively correlates with the expression pattern of Oct4, a well-established marker of pluripotency. Our observation is the first to show the heterogeneity in the mitochondrial redox state within a mESC colony, suggesting that mitochondrial redox state should be further investigated as a potential new biomarker for the stemness of embryonic stem cells.
氧化还原状态介导胚胎干细胞（ESC）的分化，因此为理解干细胞的多能性提供了一种重要的补充方法。烟酰胺腺嘌呤二核苷酸的还原形式（NADH）与氧化型黄素蛋白（Fp）的比值（NADH/（Fp + NADH））已被确立为线粒体氧化还原状态的敏感指标。在本文中，我们报告了关于小鼠胚胎干细胞（mESC）集落线粒体氧化还原状态的氧化还原成像数据及其意义。采用低温NADH/Fp氧化还原扫描仪对生长在玻璃盖玻片上经γ射线照射的小鼠胚胎成纤维细胞（MEF）饲养层上的mESC集落进行成像。结果显示，单个mESC集落（大小：约200 - 440微米）内的线粒体氧化还原状态存在显著异质性，其核心区域的还原状态比周边区域更高。这种更高的还原状态与多能性的公认标志物Oct4的表达模式呈正相关。我们的观察首次表明mESC集落内线粒体氧化还原状态存在异质性，这表明线粒体氧化还原状态应作为胚胎干细胞干性的潜在新生物标志物进行进一步研究。
