右美托咪定对A549细胞缺氧/复氧损伤时JNK的影响

目的: 观察右美托咪定(dexmedetomidine,DEX)对缺氧/复氧所致的A549细胞损伤的干预作用以及对c-Jun氨基末端激酶(JNK)的影响。方法:培养A549细胞株，将细胞随机分为4组（n=10）：正常对照组（N组），DEX组（D组），缺氧/复氧损伤组（H组），缺氧/复氧损伤+DEX干预组（HD组）。造模结束后，在倒置显微镜下观察细胞形态学的变化。CCK-8法检测A549细胞活力。原位末端标记（TUNEL）法检测A549细胞的凋亡指数（AI）。蛋白免疫印迹法（Western blot）检测细胞内葡萄糖调节蛋白78（GRP78）、p-JNK、caspase-3蛋白的表达水平，逆转录-聚合酶链反应（RT-PCR）检测GRP78、JNK mRNA的表达水平。结果:与N组比较，H组贴壁细胞数量明显减少，细胞形态发生改变。A549细胞的吸光度（OD）值明显下降（P<0.01），AI值升高（P<0.01），凋亡细胞数明显增加（P<0.01）。HD组与H组相比，细胞损伤减轻，OD值上调（P<0.01），凋亡细胞数相对减少，AI值下调（P<0.01）。p-JNK、caspase-3蛋白和JNK mRNA表达下降（P<0.01）。结论:DEX可有效减轻A549细胞缺氧/复氧损伤，机制可能与其抑制JNK通路激活所致的细胞凋亡有关。

Effects of dexmedetomidine on JNK in A549 cells with hypoxia/reoxygenation injury

AIM: To investigate the effects and c-Jun N-terminal kinase(JNK) expression of dexmedetomidine (DEX) on A549 cells with hypoxia/reoxygenation（H/R） injury. METHODS: A549 cells were cultivated and were randomly divided into four groups (n=10): control group (N), DEX group (D), hypoxia/reoxygenation injury group (H), hypoxia/reoxygenation injury+DEX interfere group (HD). After all models were completed, the morphological changes of A549 cells were observed under the inverted microscope. Cell activity was detected by CCK-8 and the apoptosis index (AI) was detected by in situ end labeling (TUNEL) method. The expression of GRP78, p-JNK, caspase-3 at protein levels and GRP78, JNK mRNA were detected by Western blot and RT-PCR.RESULTS:Compared with N group, the number of adherent cells in H group decreased significantly, and cell morphology changed. The expression of OD value in H group decreased obviously (P<0.01), the expression of AI value, GRP78, p-JNK, caspase-3 protein and GRP78, JNK mRNA were significantly increased (P<0.01). HD group compared with H group, the cell damage alleviated, the expression of OD value was increased (P<0.01), the number of apoptosis cells and the AI value in HD group were significantly decreased (P<0.01). Dramatically decreased the expression of p-JNK, caspase-3 protein and JNK mRNA (P<0.01). CONCLUSION: DEX can effectively alleviate A549 cells damage induced by H/R injury, which may be related to inhibition of the JNK pathway.