高浓度葡萄糖上调人血管内皮细胞水孔蛋白-1的表达

目的 观察高浓度葡萄糖对人血管内皮细胞水孔蛋白-1(AQP1)表达的影响。方法 用高浓度葡萄糖和高渗透压分别刺激体外培养的人脐静脉内皮细胞(HUVECs)6、24、48、72 h,观察其对AQP1蛋白和mRNA表达的影响,以未添加葡萄糖或甘露醇培养组为对照组。结果 培养6 h后,各组AQP1蛋白和mRNA的表达量无明显差别(P>0.05);培养24 h后,4.25％葡萄糖组与对照组相比,AQP1表达量明显增加(P<0.05);继续培养AQP1表达量的增加更为明显。与甘露醇培养基组比较,AQP1表达量在蛋白质水平和mRNA水平均无明显差别(P>0.05)。结论 提示体外高浓度葡萄糖可上凋人血管内皮细胞AQP1的表达,其上凋作用可能主要通过高渗透压作用介导。

Expression of AQP1 in cultured human endothelial cells is upregulated by high glucose

Objective Aquaporin-1 (AQP1) has been claimed to be the molecular counterpart of ultrasmall pore during peritoneal dialysis ( PD) . This study was done to investigate the effect of glucose on AQP1 expression in human endothelial cells. Methods Human umbilical vein endothelial cells (HUVECs) were cultured in serum-containing media until they reached subconfluence. Then the cells were exposed to the media supplemented with glucose in different concentrations or 4. 25% mannitol for 6, 24, 48,72 h. Total RNA and protein were extracted. Semi-quantative RT-PCR and Western blotting were used to detect the expression of AQP1. Results There was weak detectable AQP1 in cultured HUVECs at both mRNA and protein levels. When exposing HUVECs to high glucose for 6 h, there was no significant difference of AQP1 expression with comparison to those grown in media without glucose supplementation. But after incubation for 24 h, the expression of AQP1 was increased with increasing glucose concentration. Cells grown in media containing 4. 25% glucose showed 1.5 to 2 folds higher AQP1 expression than those grown in media without glucose supplementation (P < 0. 05). Futher increases were observed when the exposure time was prolonged to 48 h and 72 h. No difference of AQP1 expression existed between the cells grown in media containing 4. 25% glucose and 4. 25% mannitol. Conclusion The present study suggests that expression of AQP1 mRNA and protein in human endothelial cells can be upregulated by glucose. Its upregulation is mainly through hyperos-molarity.