【摘要】 目的:探讨核黄素的光敏作用对细胞端粒、端粒酶及生长活性的影响。方法:采用四甲基偶氮唑(MTT)法检测光照核黄素对Hela细胞的抑制率;细胞免疫组化法检测细胞8-羟基鸟嘌呤的生成;Southern B lot检测细胞端粒长度、端粒酶活性变化;结果:光照核黄素对Hela细胞有抑制作用且随浓度的增加抑制作用加强;受核黄素作用后细胞损伤产物8-羟基鸟嘌呤染色结果显示细胞核强阳性;细胞端粒随核黄素作用时间的延长有缩短的趋势,而端粒酶活性在开始的1h左右略有下降,而至后则有上升趋势。结论:核黄素光敏反应可造成细胞DNA富含鸟嘌呤区域羟基化损伤,该羟基化损伤与富含鸟嘌呤的端粒重复序列缩短有关。更多还原

【Abstract】 Objective:For further research of the effect of photodegradation of riboflavin to cells.Methods:The mean telomere length and the activities of telomerase were studied.MTT assay was used to estimate the inhibition rate of riboflavin.Immnohistochemical studies by detecting 8-hydroxyguanine(8-oxodG) as the marker of DNA damage.The telomere length was measured by southern blot.The activities of telomerase was measured by TRAP.Results:The result showed that The inhibition rate of tumor cells is dose-dependent of riboflavin;guanine could be oxidized into 8-hydroxyguanine in both 32 and 3.2μmol/L riboflavin-given groups;the telomere length was measured by southern blot and the results indicated that there was a continuous telomere shortens with time;in the time of 0,0.5,1,2,4h dealt with photosensitiv riboflavin,ratio of telomere shorten was 5.5%,11.2%,14%,17.8%.The activities of telomerase was lower at first 1h but had a trend to rise after that.Conclusion:The photodegrada-tion of riboflavin caused oxidized damage of G-rich region on DNA,which may related with the telomere shortening and the activities of telomerase.更多还原