新生牛肝再生刺激素对HL-60细胞DNA的损伤作用

本研究旨在观察分子量小于10kD的肝再生刺激素(hepatocyte growth-promoting substance，HGS)在体外液体培养中对HL-60细胞增殖的影响，并探讨其作用机制。实验分为3组：22．5μg/ml组、40μg/ml组和对照组，用胎盘蓝染色法计数HL-60细胞生长曲线，观察HGS对HL-60细胞增殖的影响；应用单细胞凝胶电泳法比较不同剂量HGS引起HL-60细胞的DNA损伤情况；采用基因组DNA体外电泳技术，观察HL-60细胞在HGS作用后凋亡的DNA片段断裂情况。结果表明，22．5μg/ml和40μg/ml 2个组在2天培养后均观察到HL-60细胞的增殖受到抑制；基因组DNA体外电泳结果证明，在上述2个剂量的组内，出现了明显的DNA梯形条带，并于培养第2天有HL-60细胞凋亡；单细胞凝胶电泳(SEGE)显示，HL-60细胞在加入HGS后出现有慧尾的细胞数量增多。结论：HGS能够抑制白血病细胞系HL-60细胞的增殖，并通过诱导凋亡导致DNA损伤来杀伤对HL-60细胞。

Damage Effect of Hepatocytic Growth-promoting Substance from Neonatal Calf on DNA of HL-60 cells

The present study was aimed to investigate the damage effect of hepatocyte growrh promoting substance (HGS) on the HL-60 cell DNA in vitro and to explore the possible mechanism underlying the effect. Experiment was divided into 3 groups: one was control group, in which 0.9% NaCl solution was added, and other two were experimental group 1 and group 2, where 22.5 microg/ml and 40 microg/ml HGS were added, respectively. HL-60 cell growths were compared between groups with and without HGS. Single cell gel electrophoresis (SCGE) was used to detect DNA damage of HL-60 cell. DNA electrophoresis was used to detect the apoptosis of HL-60 cells caused by HGS. The results showed that the inhibitory effects of HGS on growth of HL-60 cells were observed in group with 22.5 microg/ml and group with 40 microg/ml after culture for 2 days, the DNA ladder and the apoptosis of HL-60 cells occurred in these 2 groups on day 2 after addition of HGS, the counts of HL-60 cells with comet tail in these experimental groups were found to be more increased in comparison with control group. In conclusion, the HGS can inhibit the growth of HL-60 cell and the apoptosis of HL-60 cells should be induced through pathway of DNA damage caused by HGS.