Department of Orthopedic Surgery, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 65-1 Kumho-dong, Uijeongbu-si, Kyunggi-do, Korea, 480-717.
Int Orthop. 2014 Jun;38(6):1311-20. doi: 10.1007/s00264-014-2296-z. Epub 2014 Feb 18.
Diabetes mellitus (DM) is thought to be an important aetiological factor in intervertebral disc degeneration. A glucose-mediated increase of oxidative stress is a major causative factor in development of diseases associated with DM. The aim of this study was to investigate the effect of high glucose on mitochondrial damage, oxidative stress and senescence of young annulus fibrosus (AF) cells.
AF cells were isolated from four-week-old young rats, cultured, and placed in either 10 % FBS (normal control) or 10 % FBS plus two different high glucose concentrations (0.1 M and 0.2 M) (experimental conditions) for one and three days. We identified and quantified the mitochondrial damage and reactive oxygen species (ROS) (oxidative stress). We also identified and quantified the occurrence of senescence and telomerase activity. Finally, the expressions of proteins were determined related to replicative senescence (p53-p21-pRB) and stress-induced senescence (p16-pRB).
Two high glucoses enhanced the mitochondrial damage in young rat AF cells, which resulted in an excessive generation of ROS in a dose- and time-dependent manner for one and three days compared to normal control. Two high glucose concentrations increased the occurrence of senescence of young AF cells in a dose- and time-dependent manner. Telomerase activity declined in a dose- and time-dependent manner. Both high glucose treatments increased the expressions of p16 and pRB proteins in young rat AF cells for one and three days. However, compared to normal control, the expressions of p53 and p21 proteins were decreased in young rat AF cells treated with both high glucoses for one and three days.
The present study demonstrated that high glucose-induced oxidative stress accelerates premature stress-induced senescence in young rat AF cells in a dose- and time-dependent manner rather than replicative senescence. These results suggest that prevention of excessive generation of oxidative stress by strict blood glucose control could be important to prevent or to delay premature intervertebral disc degeneration in young patients with DM.
糖尿病（DM）被认为是椎间盘退变的重要病因。葡萄糖介导的氧化应激增加是导致与 DM 相关疾病发展的主要原因。本研究旨在探讨高血糖对年轻纤维环（AF）细胞线粒体损伤、氧化应激和衰老的影响。
从 4 周龄幼鼠中分离 AF 细胞，培养后置于 10%胎牛血清（正常对照）或 10%胎牛血清加两种不同高葡萄糖浓度（0.1 M 和 0.2 M）（实验条件）中 1 天和 3 天。我们鉴定和量化了线粒体损伤和活性氧（ROS）（氧化应激）。我们还鉴定和量化了衰老和端粒酶活性的发生。最后，测定了与复制性衰老（p53-p21-pRB）和应激诱导性衰老（p16-pRB）相关的蛋白表达。
两种高葡萄糖增强了幼鼠 AF 细胞的线粒体损伤，导致 ROS 的产生在 1 天和 3 天内呈剂量和时间依赖性增加，与正常对照组相比。两种高葡萄糖浓度在剂量和时间上均增加了幼鼠 AF 细胞衰老的发生。端粒酶活性呈剂量和时间依赖性下降。两种高葡萄糖处理均增加了幼鼠 AF 细胞中 p16 和 pRB 蛋白的表达，持续 1 天和 3 天。然而，与正常对照组相比，两种高葡萄糖处理均使幼鼠 AF 细胞中 p53 和 p21 蛋白的表达在 1 天和 3 天内减少。
本研究表明，高血糖诱导的氧化应激以剂量和时间依赖性方式加速幼鼠 AF 细胞过早的应激诱导性衰老，而不是复制性衰老。这些结果表明，通过严格的血糖控制来防止氧化应激的过度产生，对于预防或延缓年轻 DM 患者的椎间盘退变可能很重要。
