谷氨酰胺抑制过氧化氢诱导的A549细胞凋亡

目的观察谷氨酰胺诱导A549细胞表达HSP70及在抗过氧化氢（H2O2）诱导的细胞凋亡中的作用。方法体外培养A549细胞，随机分为4组：①空白对照组（C组）即生理盐水组；②谷氨酰胺组（Gln组）：以含谷氨酰胺8mmol/L的培养液预处理细胞；③过氧化氢组（H₂O₂组）：以浓度为400μmol/L过氧化氢处理细胞；④谷氨酰胺预处理后过氧化氢刺激组（Gln+H₂O₂组）：以含谷氨酰胺8mmol/L预处理细胞后，再加入400μmol/L过氧化氢处理细胞. 用免疫印记（Western blotting）法检测HSP70蛋白的表达，记录平均灰度值；用流式细胞仪Annexin-V法检测细胞凋亡,计算细胞总凋亡率。结果① 与C组HSP70表达（1.87±0.55） 相比，Gln组（8.42±1.38）、H₂O₂组（9.35±1.57）和Gln+H₂O₂组（13.12±1.85）的HSP70表达分别增高约4.5倍、5倍和7倍（P＜0.01）；与H₂O₂组HSP70表达相比，Gln+H2O2组进一步增高（P＜0.01）；②与C组相比，Gln组细胞总凋亡率无明显变化；H₂O₂组和Gln+H₂O₂组细胞总凋亡率分别为7.48%和6.06%，均明显高于C组（P＜0.01）；与H₂O₂组相比，Gln+H₂O₂组细胞总凋亡率明显降低（P＜0.01）。结论谷氨酰胺诱导A549细胞表达HSP70并可明显地抑制H2O2所致的细胞凋亡作用。

Glutamine inhibits the apoptosis A549 cells induced by H2O2

ObjectiveTo explore the effects of heat shock protein 70 induced by glutamine on the apoptosis of cultured A549 cells induced by hydrogen peroxide （H₂O₂）. MethodsCultured A549 cells were divided into four groups: the physiologic saline group (C group), the glutamine group (Gln group), the H₂O₂ group and the Gln+H2O2 group. Western blotting was used to determine the expression of HSP70. Flow cytometry and Annexin-V were used to determine the apoptosis. Results① Compared with the expression of HSP70 in the C group（1.87±0.55）, the expression of HSP70 increased 4.5 times, 5 times and 7 times in the Gln group（8.42±1.38）, the H₂O₂ group（9.35±1.57）and the Gln+H₂O₂ group（13.12±1.85）, respectively. Also the expression of HSP70 in the H₂O₂+Gln group was higher than that in the H₂O₂ group（P＜0.01）. ② Compared with the C group,　the apoptosis of cells in the Gln group had not changed（P＞0.05）, while the apoptosis of cells in the H₂O₂ and the Gln+H₂O₂ groups significantly increased(P＜0.01).Compared with the H₂O₂ group, the apoptosis of cells in the Gln+H₂O₂ group significantly decreased(P＜0.01). ConclusionsGlutamine can enhance the expression of HSP70 in A549 cells and inhibit the apoptosis induced by hydrogen peroxide.