α-硫辛酸增强吡咯烷二硫代氨基甲酸对Hep-2细胞增殖的抑制作用

α-Lipoic acid promotes inhibition of pyrrolidine dithiocarbamic acid on Hep-2 cell proliferation

目的：探讨α-硫辛酸（α-LA）对吡咯烷二硫代氨基甲酸（PDTC）抑制Hep-2细胞增殖的影响。方法体外培养人喉癌细胞系Hep-2细胞，加入α-LA、PDTC或α-LA联合PDTC作用12，24和48h后，用WST-1法和软琼脂集落形成法检测细胞增殖，Hoechst33258染色法和流式细胞仪检测细胞凋亡和细胞周期。结果α-LA5~500μmol·L-1对Hep-2细胞增殖无抑制作用，PDTC5-50μmol·L-1能明显抑制Hep-2细胞增殖（P﹤0.05，P﹤0.01），PDTC5μmol·L-1联合α-LA5，10和20μmol·L-1对Hep-2细胞增殖的抑制率明显高于对照组（P﹤0.01）和PDTC单独处理组（P﹤0.05）。PDTC5μmol·L-1与α-LA5μmol·L-1联合用药，在12~48h内对Hep-2细胞增殖的抑制率呈时间依赖性（r＝0.987，P﹤0.05），24h后软琼脂细胞集落形成数与PDTC单独处理（P﹤0.05）和α-LA单独处理组相比明显减少（P﹤0.01）。Hoechst33258染色和流式细胞仪检测结果表明，与PDTC和α-LA单独处理组比较，PDTC5μmol·L-1与α-LA5μmol·L-1联合用药24h凋亡细胞增加，G2/M期细胞百分率增加（P﹤0.05）。结论α-LA可增强PDTC对Hep-2细胞增殖的抑制作用并诱导Hep-2细胞凋亡。

OBJECTIVE To investigate whether α-lipoic acid（α-LA）can promote the anti-prolifera-tion effect of pyrrolidine dithiocarbamic acid（PDTC）in Hep-2 cells. METHODS The laryngeal carcino-ma Hep-2 cells were cultured with α-LA,PDTC or α-LA＋PDTC respectively for 12,24 and 48 h. The proliferation of Hep-2 cells was detected by WST-1 assay and soft agar colony formation while apoptosis and cell cycle were analyzed by Hoechst33258 staining and flow cytometry. RESULTS α-LA 5 -500 μmol·L-1 could not inhibit Hep-2 cell proliferation,but PDTC 5 -50 μmol·L-1 could（ P ﹤0.05,P ﹤0.01）. The cell proliferation inhibitory rate of PDTC 5 μmol·L-1 combined with α-LA 5,10 and 20 μmol·L-1 groups was much higher than in control group（P﹤0.01）and PDTC alone group（P﹤0.05）. When α-LA 5 μmol·L-1 was used in combination with PDTC 5 μmol·L-1 for 12-48 h,the cell proliferation was inhibited in a time-dependent manner（r=0.987,P﹤0.05）. When the cells were treated for 24 h,the number of soft agar colony formations in combined group was significantly smaller than that of both α-LA alone group（P﹤0.01）and PDTC alone group（P﹤0.05）. The result of Hoechst33258 staining and flow cytometry indicated that after combined treatment with PDTC 5 μmol·L-1 and α-LA 5 μmol·L-1 for 24 h,the level of apoptosis and the percentage of cells in G2 / M stage were significantly increased compared with PDTC alone or α-LA alone treatment. CONCLUSION α-LA can enhance the anti-proliferation and pro-apoptosis effect of PDTC in Hep-2 cells.