Koninkx J F, Brown D S, Kok W, Hendriks H G, Pusztai A, Bardocz S
Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Utrecht, The Netherlands.
Gut. 1996 Jan;38(1):47-52. doi: 10.1136/gut.38.1.47.
The effect of Phaseolus vulgaris isolectin E4 on polyamine concentrations and ornithine decarboxylase activity of proliferating and differentiating Caco-2 cells was investigated. Values of putrescine, spermidine, and spermine in control cells were highest during the early phase of proliferative cell growth and lowest in the stationary phase. Phytohaemagglutinin E4 significantly increased cellular polyamine values during the late proliferative phase of cell growth. Ornithine decarboxylase activity was high during intensive proliferation and growth, but was lower when proliferation slowed down or ceased. Exposure of Caco-2 cells in the early proliferative phase of cell growth to increasing concentrations of the potent intestinal growth factor phytohaemagglutinin E4 greatly stimulated enzyme activity. In contrast, the activity of ornithine decarboxylase was not stimulated in Caco-2 cells of the late proliferative phase nor was there any increase in the enzyme activity in differentiating and fully differentiated cells of the stationary phase. Accordingly, when proliferating Caco-2 cells possessed the highest ornithine decarboxylase activity, the polyamine values were also at their highest. During differentiation, as the ornithine decarboxylase activity fell close to zero, polyamine values also decreased. In the early proliferative phase of cell growth ornithine decarboxylase activity coincided with DNA synthesis in cells exposed to Phaseolus vulgaris isolectin E4. These findings with Caco-2 cells were similar to those found in brush border cells of the rat small intestine.
研究了菜豆异凝集素E4对增殖和分化的Caco-2细胞中多胺浓度及鸟氨酸脱羧酶活性的影响。对照细胞中腐胺、亚精胺和精胺的值在增殖性细胞生长的早期阶段最高，而在静止期最低。植物血凝素E4在细胞生长的增殖后期显著增加了细胞多胺值。鸟氨酸脱羧酶活性在细胞大量增殖和生长期间较高，但在增殖减缓或停止时较低。在细胞生长的早期增殖阶段，将Caco-2细胞暴露于浓度不断增加的强效肠道生长因子植物血凝素E4中，可极大地刺激酶活性。相反，在增殖后期的Caco-2细胞中，鸟氨酸脱羧酶活性未受到刺激，在静止期的分化细胞和完全分化细胞中该酶活性也未增加。因此，当增殖的Caco-2细胞具有最高的鸟氨酸脱羧酶活性时，多胺值也处于最高水平。在分化过程中，随着鸟氨酸脱羧酶活性降至接近零，多胺值也下降。在细胞生长的早期增殖阶段，鸟氨酸脱羧酶活性与暴露于菜豆异凝集素E4的细胞中的DNA合成一致。这些关于Caco-2细胞的发现与在大鼠小肠刷状缘细胞中发现的结果相似。
