Chiba Yoichi, Yamashita Yoshinori, Ueno Masaki, Fujisawa Hiromi, Hirayoshi Kazunori, Hohmura Ken-Ichi, Tomimoto Hidekazu, Akiguchi Ichiro, Satoh Mamoru, Shimada Atsuyoshi, Hosokawa Masanori
Department of Neurology, Graduate School of Medicine, Kyoto University, Japan.
J Gerontol A Biol Sci Med Sci. 2005 Sep;60(9):1087-98. doi: 10.1093/gerona/60.9.1087.
The senescence-accelerated mouse is a model for senescence acceleration, a higher oxidative stress status, and age-associated disorders. We studied whether fibroblasts cultured from accelerated senescence-prone SAMP11 mice could be used as in vitro models for oxidative stress in senescence. Dichlorofluorescein and hydroethidine assays demonstrated that cells from SAMP11 mice produced more reactive oxygen species than did cells from accelerated senescence-resistant SAMR1 mice. These differences were not due to the defective induction of antioxidants. Double labeling with hydroethidine and MitoTracker Green revealed that most of the reactive oxygen species were generated within the mitochondria. Nonyl acridine orange and JC-1 assays showed an increase in the mass of the mitochondria, especially those with low membrane potential, in SAMP11 cells. Ultrastructurally, mitochondria with degenerative morphology were increased in SAMP11 cells with longer culture periods. These results suggest that cells from SAMP11 mice are useful models for spontaneous higher oxidative stress in vitro due to dysfunctional mitochondria.
衰老加速小鼠是衰老加速、氧化应激状态较高以及与年龄相关疾病的模型。我们研究了从易发生加速衰老的SAMP11小鼠培养的成纤维细胞是否可作为衰老过程中氧化应激的体外模型。二氯荧光素和氢乙啶检测表明,SAMP11小鼠的细胞比抗加速衰老的SAMR1小鼠的细胞产生更多的活性氧。这些差异并非由于抗氧化剂诱导缺陷所致。用氢乙啶和MitoTracker Green进行双重标记显示,大部分活性氧在线粒体内产生。壬基吖啶橙和JC-1检测表明,SAMP11细胞中线粒体的质量增加,尤其是那些膜电位较低的线粒体。在超微结构上,培养时间较长的SAMP11细胞中具有退行性形态的线粒体增多。这些结果表明,由于线粒体功能失调,SAMP11小鼠的细胞是体外自发性较高氧化应激的有用模型。