用原位缺口翻译法研究棉酚、雷公藤总甙对DNA的损伤作用

STUDIES ON THE EFFECTS OF GOSSYPOL AND GLYCOSIDES TRIPTERYGIUM WILFORDII(GTW) ON DNA BY IN SITU NICK TPANSLATION METHOD

本文报道用原位缺口翻译法,研究男用节育药醋酸棉酚和雷公藤总甙(GTW)对C3H-10 T 1/2小鼠成纤维细胞DNA的作用。结果表明,在较高浓度的醋酸棉酚或GTW(2～3μg/ml)作用4小时,细胞核中显示的银颗粒较多,如阳性对照组的N-甲基-N′-硝基-亚硝基胍(MNNG)组;在中等浓度的(0.5～1μg/ml)作用下,银颗粒显著地少得多;在较低浓度的醋酸棉酚或GTW作用下(0.1～0.3μg/ml),细胞核中呈现的银颗粒与阴性对照组相似。与原位缺口翻译实验相对应,集落形成试验表明,在高浓度醋酸棉酚或GTW作用下,细胞失去繁殖的能力;而在中等或较低浓度的药物作用下,仍有较高的集落形成率。这些观察表明,高浓度的醋酸棉酚或GTW对细胞DNA有严重的损伤作用,而在中等浓度的药物作用下,DNA受到某种程度的损伤,但可修复;低浓度的醋酸棉酚或GTW对细胞DNA无明显的损伤作用,本文对这些结果的意义进行了简要的讨论。

The present study reported the effect of two male antifertility agents gossypol acetic acid and GTW on DNA of C3H10T1/2 mouse fibroblasts. Our results showed that the cells treated with gossypol or GTW at high concentration (2-3 μg/ml) for 4 hours, show silver grains in their nuclei as much as the positive control group, N-methyl N′-nitro-N-nitrosoguanidine (MNNG) a known carcinogen. However, if the agents were used at moderate concentrations (0.5-1μg/ml), the silver grains were much less, if the concentrations of gossypol or GTW were of 0.1-0.3 μg/ml, the silver grains were as less as the control group. In a colony-forming test, we found that the cells lost their proliferate ability, since no colonies could be formed, if gossypol or GTW were of high concentration; while at moderate or low concentrations, the colony-forming rate was as high as 8.1-10.5％. Taking all of these results into consideration, we suggest that high concentrations of gossypol or GTW can damage cell DNA severely, moderate concentration of the agents break cell DNA to a certain extent, but the cells can repair, while low concentration of gossypol or GTW exert no obvious effect on cells. The significance of these observations was briefly discussed.