Choo H-J, Kim J-H, Kwon O-B, Lee C S, Mun J Y, Han S S, Yoon Y-S, Yoon G, Choi K-M, Ko Y-G
Graduate School of Life Sciences and Biotechnology, Korea University, 1, 5-ka, Anam-dong, Sungbuk-gu, Seoul, 136-701, South Korea.
Diabetologia. 2006 Apr;49(4):784-91. doi: 10.1007/s00125-006-0170-2. Epub 2006 Feb 25.
AIMS/HYPOTHESIS: The aim of this study was to confirm a link between mitochondrial dysfunction and type 2 diabetes.
Cellular levels of mitochondrial proteins, cellular mitochondrial DNA content, and mitochondrial function and morphology were assessed by MitoTracker staining and electron microscopy, in white adipose tissue of 12-week-old male wild-type, obese (ob/ob), and diabetic (db/db) mice.
Levels of mitochondrial proteins were found to be very similar in the livers and muscles of all the mice studied. However, levels were greatly decreased in the adipocytes of db/db mice, but not in those of the wild-type and ob/ob mice. Levels of mitochondrial DNA were also found to be considerably reduced in the adipocytes of db/db mice. MitoTracker staining and under electron microscopy revealed that the number of mitochondria was reduced in adipocytes of db/db mice. Respiration and fatty acid oxidation studies indicated mitochondrial dysfunction in adipocytes of db/db mice. Interestingly, there was an increase in mitochondria and mitochondrial protein production in adipocytes of db/db mice treated with rosiglitazone, an agent that enhances insulin sensitivity.
CONCLUSIONS/INTERPRETATION: Taken together, these data indicate that mitochondrial loss in adipose tissue is correlated with the development of type 2 diabetes.
目的/假设：本研究的目的是证实线粒体功能障碍与2型糖尿病之间的联系。
通过MitoTracker染色和电子显微镜评估12周龄雄性野生型、肥胖（ob/ob）和糖尿病（db/db）小鼠白色脂肪组织中线粒体蛋白的细胞水平、细胞线粒体DNA含量以及线粒体功能和形态。
在所研究的所有小鼠的肝脏和肌肉中，线粒体蛋白水平非常相似。然而，db/db小鼠脂肪细胞中的水平大幅下降，而野生型和ob/ob小鼠的脂肪细胞中则没有。还发现db/db小鼠脂肪细胞中的线粒体DNA水平显著降低。MitoTracker染色和电子显微镜显示db/db小鼠脂肪细胞中的线粒体数量减少。呼吸和脂肪酸氧化研究表明db/db小鼠脂肪细胞存在线粒体功能障碍。有趣的是，用增强胰岛素敏感性的药物罗格列酮治疗的db/db小鼠脂肪细胞中的线粒体和线粒体蛋白产量增加。
结论/解读：综上所述，这些数据表明脂肪组织中的线粒体丢失与2型糖尿病的发生有关。
