Yi Tong-ning, Zhang Jin, Yu Shi-jia, Gao Tian-shu
Department of Endocrinology and Metabolism, the Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang 110031, Liaoning, China.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue. 2011 May;23(5):275-8.
To investigate the changes in reactive oxygen species (ROS) and dimethyl- arginine dimethylaminohydrolase-asymmetric dimethylarginine (DDAH-ADMA) system in the process of endothelial cell senescence after exposure to high glucose.
The human umbilical vein endothelial cells (HUVECs) were cultured with different concentrations of glucose, e.g. 5.5 mmol/L (normal level), and high levels as 11.0, 22.0 and 33.0 mmol/L, for 48 hours, respectively. Subsequently, SA-β-gal staining was used to evaluate senescence of cells. Telomerase activity was detected by polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA). The intracellular ROS level was measured by flow cytometry. The ADMA concentration and DDAH activity were determined with high-performance liquid chromatography.
Compared with normal glucose concentration group, after the endothelial cells were treated with high glucose concentration (11.0-33.0 mmol/L) for 48 hours, the number of SA-β-gal positive cells was increased significantly [(7.00±1.73)%, (12.67±2.03)%, (16.00±2.26)% vs. (4.00±1.33)%, P>0.05, P<0.05, P<0.05] and the telomerase activity was inhibited dramatically [(91.32±4.01)%, (78.44±3.78)%, (56.04±3.35)% vs. 100%, all P<0.05]. The ROS level (mfi) was increased in all high glucose groups (159.84±27.52, 188.99±18.77, 244.56±20.96 vs.117.11±18.76, P<0.05 or P<0.01). At the same time, the ADMA (μmol/L) production was increas ed (0.78±0.14, 0.88±0.18, 1.08±0.15 vs. 0.70±0.12, P>0.05, P<0.05, P<0.05), and DDAH activity was decreased [(91.32±4.01)%, (78.44±3.78)%, (56.04±3.35)% vs.100%, all P<0.05].
High glucose can accelerate endothelial cells senescence in dose-dependent manner and the underlying mechanism may be related to an increased oxidative stress and change in DDAH-ADMA system.
探讨高糖环境下内皮细胞衰老过程中活性氧（ROS）及二甲基精氨酸二甲胺水解酶-不对称二甲基精氨酸（DDAH-ADMA）系统的变化。
将人脐静脉内皮细胞（HUVECs）分别用不同浓度葡萄糖（5.5 mmol/L，正常水平；11.0、22.0和33.0 mmol/L，高水平）培养48小时。随后，采用SA-β-gal染色评估细胞衰老情况。通过聚合酶链反应-酶联免疫吸附测定（PCR-ELISA）检测端粒酶活性。采用流式细胞术测定细胞内ROS水平。用高效液相色谱法测定ADMA浓度和DDAH活性。
与正常葡萄糖浓度组相比，内皮细胞经高糖浓度（11.0 - 33.0 mmol/L）处理48小时后，SA-β-gal阳性细胞数量显著增加[（7.00±1.73）%，（12.67±2.03）%，（16.00±2.26）% 对 （4.00±1.33）%，P>0.05，P<0.05，P<0.05]，端粒酶活性受到显著抑制[（91.32±4.01）%，（78.44±3.78）%，（56.04±3.35）% 对100%，均P<0.05]。所有高糖组的ROS水平（平均荧光强度）均升高（159.84±27.52，188.99±18.77，244.56±20.96对117.11±18.76，P<0.05或P<0.01）。同时，ADMA（μmol/L）生成增加（0.78±0.14，0.88±0.18，1.08±0.15对0.70±0.12，P>0.05，P<0.05，P<0.05），DDAH活性降低[（91.32±4.01）%，（78.44±3.78）%，（56.04±3.35）% 对100%，均P<0.05]。
高糖可呈剂量依赖性加速内皮细胞衰老，其潜在机制可能与氧化应激增加及DDAH-ADMA系统变化有关。
