葡萄糖对内皮细胞醛糖还原酶基因表达及活性的影响

目的研究葡萄糖对人血管内皮细胞醛糖还原酶基因表达及活性的影响,为糖尿病血管并发症提供理论依据。方法体外培养的人脐静脉内皮细胞,采用RT-PCR、生化测定等方法检测醛糖还原酶(AR)活性及mRNA表达。结果经5·5、11、22mmol/L葡萄糖处理后内皮细胞AR的mRNA及其活性均高于对照组(5.5mmol/L葡萄糖)(P<0.05或P<0.01),呈浓度依赖性,但44mmol/L葡萄糖组较22mmol/L葡萄糖组低(P<0.05)。在22mmol/L葡萄糖作用下,随着作用时间的延长(0、12、24h),AR的mRNA及活性增高呈时间依赖性(P<0.05或P<0.01),但48h较24h低(P<0.05)。结论葡萄糖能诱导内皮细胞AR基因表达,增强AR活性,且在一定范围内呈时间及浓度依赖性。

The Effects of Glucose on Gene Expression and Activity of Aldose Reductase in Endothelial Cells

Objective To study the effects of glucose on gene expression and activity of aldose reductase (AR) in endothelial cells. Methods Human umbilical vein endothelial cells (HUVECs) were cultured in vitro. The activity of AR gene expression in mRNA level in HUVECs were measured by RT-PCR and biochemical assay. Results The AR mRNA levels and its activity increased in dose-depended manner in endothelial cells incubated for 24h with 11mmol/L,22mmol/L glucose, compared with those in 5.5 mmol/L glucose ( P <0.05 or P <0.01). AR mRNA levels and its activity in HUVECs cultured with in 44mmol/L glucose for 24h lower than those in 22mmol/L glucose for 24h ( P <0.05). The AR mRNA levels and its activity increased in time-depended manner in endothelial cells incubated with 22mmol/L glucose for 12h, 24h, compared with those in 22mmol/L glucose for 0h( P <0.05 or P <0.01). AR mRNA levels and its activity in HUVECs cultured with in 22mmol/L glucose for 48h lower than those in 22mmol/L glucose for 24h ( P <0.05). Conclusion Glucose can upregulate AR gene expression and enhance its activity in dose-depended and time-depended manners.