二氧化碳培养环境对A549细胞周期、肺泡表面活性蛋白C前体蛋白合成的影响

The effect of different carbon dioxide culture environmental on the cell cycle of A549 cells, pulmonary surfactant protein C precursor protein synthesis

目的 观察CO2培养浓度对A549细胞周期、合成肺泡表面活性蛋白C前体蛋白（proSP-C）的影响.方法 A549细胞按CO2培养浓度分为：A组（5％CO2）;B组（10％ CO2）;C组（18％CO2）.各组在CO2培养24、36、48 h后,采用噻唑蓝（MTT）比色法检测细胞活性;流式细胞仪检测细胞周期和凋亡率;Western blot法检测细胞内proSP-C的水平.结果 （1）与A组MTT值（0.38±0.02、0.53±0.03、0.75 ±0.03）比较,B组各观测点的值（0.42±0.03、0.56±0.03、0.78±0.04）均增高（P＜0.01）;C组的值（0.49±0.04、0.67±0.05）则在36、48 h降低（P＜0.01,P＜0.05）.（2）与A组比较,B组G1峰率和凋亡率在24、36、48 h,差异无统计学意义（P＞0.05）;C组G1峰升高在24、36 h（68.00±6.20、71.00±2.00）出现（P＜0.01,P＜0.05）,并于36、48 h凋亡率（10.00±1.20、12.80±2.60）增加（P＜0.05）.（3）B组（0.63±0.20、0.65±0.18、0.55±0.11）与A组细胞中pfoSP-C在各时点（0.58±0.15、0.63±0.09、0.55±0.11）差异无统计学意义（P＞0.05）.C组proSP-C在36、48 h（0.31±0.14、0.23±0.02）出现明显下降（P＜0.05）.结论 一定的CO2浓度升高增加A549细胞的活性,但不影响细胞周期及凋亡率;过高的CO2浓度可抑制proSP-C合成,降低细胞活性和增加凋亡率.

Objective To investigate the effect of different carbon dioxide culture environmental on the cell cycle of A549 cells,pulmonary surfactant protein C precursor protein synthesis.Methods A549 cells were subjected to 5% CO2 （group A）,10% CO2 （group B） or 18% CO2 （group C）.After 24,36 and 48 h of CO2 intervention,the survival state of those cells was estimated by MTT assay,the precursor protein of surfactant protein-C （proSP-C） was measured by Western blotting,the cell cycle progression and apoptosis were measured by flow cytometric analysis.Results （1） Compared with Group A （0.38 ± 0.02,0.53 ± 0.03,0.75 ± 0.03）,group B （0.42 ± 0.03,0.56 ± 0.03,0.78 ± 0.04） had more activity during three experimental periods （P 〈 0.01） and group C had a lower activity （0.49 ± 0.04,0.67 ± 0.05） at 36,48 h （P 〈 0.01,P 〈 0.05）.（2） Compared with A group,B group＇ s G1 peak and the rate of apoptosis in 24h,36 h and 48 h showed no significant difference （P 〉 0.05）.In the C group,The G1 peak （68.00±6.20,71.00 ±2.00） increase in 24 h and 36 h （P〈0.05）,and the Apoptosis rate （10.00 ± 1.20,12.80 ±2.60） increased in 36 h and 48 h （P 〈0.05）.（3） In the group B,the expression of proSP-C in A549 cells （0.63 ± 0.20,0.65 ± 0.18,0.55 ± 0.11） did not show any statistical difference with A group （0.58 ±0.15,0.63 ±0.09,0.55 ±0.11） （P〉0.05）.In the group C,proSP-C （5.70 ± 0.75） did not make any changes in 24 h （P〉 0.05）,however,they decreased （0.31 ± 0.14,0.23 ± 0.02） at 36 h and 48 h （P 〈 0.05）.Conclusion （1） A certain CO2 concentration increased the activity of A549 cells,but did not affect the cell cycle and apoptosis rate.（2） High CO2 concentration can inhibit proSP-C synthesis,decrease cell activity and increase apoptosis rate.