乙酰半胱氨酸对人肺成纤维细胞增殖及胶原合成的影响

The effects of N-acetylcysteine on proliferation and collagen synthesis of human lung fibroblast

目的研究乙酰半胱氨酸（NAC）对人肺成纤维细胞（HLF）增殖、凋亡和胶原合成的影响。方法分离培养HLF，经不同浓度NAC（5、10、20、40mmol／L）处理后，四氮甲基偶氮唑蓝（MTT）检测细胞增殖，流式细胞仪检测细胞凋亡、细胞周期，RT—PCR检测Ⅰ型前胶原mRNA表达的变化。结果①5、10、20、40mmol／L的NAC对HLF细胞生长均有明显抑制作用，且呈剂量依赖性。②5、10、20、40mmol／L的NAC作用24h后，细胞凋亡率分别为（34．38±5．80）％、（37．72±3．10）％、（44．05±4．52）％和（59．18±5．24）％，均明显高于对照组[（3．92±1．24）％]，差异有统计学意义（P均〈0．01）。③10、20、40mmol／L的NAC能够引起G0／G1期细胞比例明显升高，S期比例明显降低，差异有统计学意义（P均〈0．01）。④5、10、20及40mmol／L的NAC处理组HLFI型前胶原mRNA表达均明显低于对照组，差异有统计学意义（P均〈0．01）。结论NAC可直接抑制成纤维细胞增殖、诱导其发生凋亡，并降低其胶原合成。

Objective To study the effects of N-acetylcysteine （NAC） on the proliferation, apoptosis and collagen synthesis of human lung fibroblast（HLF）. Methods HLF was primarily cultured in complete medium of DMEM/F12. Different concentrations of NAC （5,10,20,40mmol/L） were administrated. Cell proliferations were tested by methyhhiazolyltetrazolium （MTT） ,apoptosis and cell cycle were detected with Flow cytometer and mRNA expression of type I procollagen with RT-PCR. Results （1）The growth of the HLF was inhibited by NAC at different concentrations （5,10,20 and 40 mmol/L ）. （2）After administration of NAC at different concentrations （ 5,10,20 and 40 mmol/L ） after 24 hours, the apoptosis rates were （ 34.38 ± 5.80） %, （ 37.72 ± 3.10） %, （44.05 ± 4.52 ）% and （59.18 ± 5.24）% ） respectively,significantly higher than that of the controls （3.92 ± 1.24）% （P 〈 0.01 ）. （3） The proportion of cells in G0/G1 phase were increased by NAC at different concentrations （10,20 and 40 mmol/L ） ,while the changes ratio in S-phase were decreased significantly（ P 〈 0.01 ） . （4）The mRNA expression of type I procollagen in HLF was decreased significantly after administration of NAC at 5, 10, 20, 40 mmol/L respectively （P 〈 0.01 ）. Conclusion Administration of NAC induces apoptosis and directly inhibites the proliferation and the collagen synthesis of HLF.