Liang Guang-Ping, Su Yong-Yue, Chen Jian, Chen Wei, Luo Xiang-Dong, Yang Zong-Cheng
Institute of Burn Research, State Key Laboratory of Trauma, Burns and Combined Injury, Southwest Hospital, Third Military Medical University, Chongqing 400038, P. R. China.
Zhonghua Shao Shang Za Zhi. 2007 Apr;23(2):130-2.
To investigate the influence of hypoxia on the proliferation and activity of human umbilical vein vascular endothelial cells (EA. hy926).
EA. hy926 cells were cultured in vitro and divided into normal control and hypoxia groups. The cells in hypoxia group were placed into hypoxic jar and treated with mixed gases(94% N2 +5% CO2 + 1% O2) for 1,3,6 and 12 hours. Then the total proteins were extracted for the determination of the expression of vascular endothelial growth factor (VEGF) and proliferation cell nuclear antigen (PCNA). The cell cycle and growth curve were determined with flow cytometry and MTT method, respectively.
The expression of PCNA protein began to increase at 3 post-hypoxia hour (PHH), peaked at 6 PHH, but without obvious difference compared with that at 12 PHH. The expression of VEGF began to increase at 1 PHH, peaked at 6 PHH, and decreased at 12 PHH, though it was still markedly higher than that of normoxia at 12 PHH. MTT results showed that the cell activity began to increase at 1 PHH, and it was still to increased at 3 PHH, then decreased at 6 PHH, and it was lower than that in control group at 12 PHH. The number of cells in G0/G1 phase was decreased, but the cells in S and G2/M phase was increased at 1, 3, 6 PHH when compared with those in normal controls. The proliferation index (PI) of cells in hypoxia group at 1PHH (43 +/- 9)%, 3PHH (39 +/- 11)%, 6 PHH (40 +/- 11))% were higher than that before hypoxia (32 +/- 9)% and 3 (39 +/- 11) % and 6 hours (40 +/- 11)% after hypoxia (P < 0.05). The PI was obviously lower at 12 PHH (27 +/- 4))% compared with that of cells under normoxic condition (P < 0.05).
Short-term hypoxia is beneficial to promote the proliferation of the cells, but this effect will be inhibited with the prolongation of hypoxia.
探讨缺氧对人脐静脉血管内皮细胞（EA.hy926）增殖及活性的影响。
体外培养EA.hy926细胞，分为正常对照组和缺氧组。将缺氧组细胞置于缺氧罐中，用混合气体（94%N₂ + 5%CO₂ + 1%O₂）处理1、3、6和12小时。然后提取总蛋白，测定血管内皮生长因子（VEGF）和增殖细胞核抗原（PCNA）的表达。分别采用流式细胞术和MTT法测定细胞周期和生长曲线。
PCNA蛋白表达在缺氧后3小时开始增加，6小时达到峰值，但与12小时相比无明显差异。VEGF表达在缺氧后1小时开始增加，6小时达到峰值，12小时下降，尽管12小时时仍明显高于常氧组。MTT结果显示，细胞活性在缺氧后1小时开始增加，3小时仍增加，6小时下降，12小时低于对照组。与正常对照组相比，在缺氧后1、3、6小时，G0/G1期细胞数量减少，S期和G2/M期细胞数量增加。缺氧组细胞在缺氧后1小时（43±9）%、3小时（39±11）%、6小时（40±11）%的增殖指数（PI）高于缺氧前（32±9）%以及缺氧后3小时（39±11）%和6小时（40±11）%（P<0.05）。与常氧条件下的细胞相比，12小时时PI明显降低（27±4）%（P<0.05）。
短期缺氧有利于促进细胞增殖，但随着缺氧时间的延长，这种作用会受到抑制。
