Cho Young Min, Kwon Sujin, Pak Youngmi Kim, Seol Hye Won, Choi Young Min, Park Do Joon, Park Kyong Soo, Lee Hong Kyu
Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea.
Biochem Biophys Res Commun. 2006 Oct 6;348(4):1472-8. doi: 10.1016/j.bbrc.2006.08.020. Epub 2006 Aug 14.
Embryonic cells before implantation are exposed to a hypoxic condition and dependent on anaerobic metabolism. Human embryonic stem cells (HESCs) derived from pre-implantation blastocyst also grow well in hypoxic conditions. Expecting that the differentiating HESCs might mimic anaerobic-to-aerobic metabolic transition of the early human life, we examined the mitochondria-related changes in these cells. We observed that mitochondrial mass and mitochondrial DNA content were increased with differentiation, which was accompanied by the increase of the amount of ATP (4-fold) and its by-product reactive oxygen species (2.5-fold). The expression of various antioxidant enzymes including mitochondrial and cytoplasmic superoxide dismutases, catalase, and peroxiredoxins showed a dramatic change during the early differentiation. In conclusion, HESC differentiation was followed by dynamic changes in mitochondrial mass, ATP and ROS production, and antioxidant enzyme expressions. Therefore, the HESCs would serve as a good model to examine the mitochondrial biology during the early human differentiation.
植入前的胚胎细胞处于缺氧状态，依赖无氧代谢。源自植入前囊胚的人类胚胎干细胞（HESC）在缺氧条件下也能良好生长。鉴于分化中的HESC可能模拟人类早期生命从无氧到有氧的代谢转变，我们研究了这些细胞中线粒体相关的变化。我们观察到，随着分化，线粒体质量和线粒体DNA含量增加，同时ATP量增加了4倍，其副产物活性氧增加了2.5倍。包括线粒体和细胞质超氧化物歧化酶、过氧化氢酶和过氧化物酶在内的各种抗氧化酶的表达在早期分化过程中发生了显著变化。总之，HESC分化后线粒体质量、ATP和ROS产生以及抗氧化酶表达发生了动态变化。因此，HESC将成为研究人类早期分化过程中线粒体生物学的良好模型。
