Putrescine stimulates DNA synthesis in intestinal epithelial cells.
Putrescine stimulates DNA synthesis in intestinal epithelial cells.
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腐胺刺激肠上皮细胞中的 DNA 合成。
DOI：
10.1152/ajpgi.1989.257.1.g145
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Seidel,ER
中科院分区：
文献类型：
--
作者：
Ginty,DD;Osborne,DL;Seidel,ER
实验旨在检查外源腐胺对培养上皮细胞 (IEC-6) 中 DNA、RNA 和蛋白质合成的影响。腐胺在浓度低至 0.3 µM 腐胺时可增加阿菲迪霉素敏感的 DNA 合成，并在 10 µM 时产生最大刺激（267% 对照）。这种反应似乎是细胞内腐胺浓度增加的结果，因为细胞内亚精胺和精胺的水平在检查的时间段内没有变化。此外，脉冲追踪实验表明，进入细胞的腐胺没有代谢成另一种多胺或降解。此外，10 µM 腐胺分别增强了放线菌酮敏感的赖氨酸掺入和放线菌素 D 敏感的尿苷掺入，分别是蛋白质和 RNA 合成的指标。添加腐胺后 12 小时，赖氨酸和尿苷的掺入达到最大，而胸苷掺入在 24 小时（所检查的最长时间点）时仍在增加。这些数据表明，粘膜增殖期间的腐胺合成和/或转运直接参与刺激上皮DNA、RNA和蛋白质合成。
Experiments were designed to examine the effects of exogenously supplied putrescine on the synthesis of DNA, RNA, and protein in cultured epithelial cells (IEC-6). Putrescine increased aphidicolin-sensitive DNA synthesis at concentrations as low as 0.3 microM putrescine with maximal stimulation (267% control) at 10 microM. This response appeared to be an effect of increases in the intracellular concentration of putrescine as the intracellular levels of spermidine and spermine did not change over the time period examined. Furthermore, pulse-chase experiments revealed that putrescine that entered the cell was not metabolized to another polyamine or degraded. In addition, 10 microM putrescine enhanced both cycloheximide-sensitive lysine incorporation and actinomycin D-sensitive uridine incorporation, indexes of protein and RNA synthesis, respectively. Incorporation of both lysine and uridine was maximal 12 h after the addition of putrescine, whereas thymidine incorporation was still increasing at 24 h, the longest time point examined. These data suggest that putrescine synthesis and/or transport during mucosal proliferation is directly involved in the stimulation of epithelial DNA, RNA, and protein synthesis.