波动性高糖对内皮细胞自噬基因表达的影响

【目的】探讨波动性高糖对内皮细胞自噬的影响及其可能的机制。【方法】体外培养人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVEC)用于实验。实验分正常对照组(5.5 mmol/L葡萄糖)和葡萄糖交替处理组(5.5/28 mmol/L葡萄糖)。其中葡萄糖交替处理模拟人血糖波动状态,方案是前12 h内每隔4 h交替培养,后12 h内葡萄糖维持5.5 mmol/L水平,按此循环,共培养48 h。用CCK-8检测细胞活性,酶标仪检测氧化应激相关指标,实时荧光定量PCR检测自噬相关基因的表达情况。【结果】与正常对照组相比,葡萄糖交替处理组降低HUVEC细胞活性(P<0.01);降低细胞内抗氧化酶活性,增加丙二醛和8-羟基脱氧鸟苷的含量(P<0.01);增加自噬相关基因Atg4和Atg5的表达(P<0.001)。【结论】波动性高糖可能是先通过诱导HUVEC产生氧化应激,进而使HUVEC产生自噬,最终降低细胞活性。

Effects of fluctuant hyperglycemia on autophagy of endothelial cells

Objective]To investigate the effect of fluctuant hyperglycemia on autophagy of endothelial cells and its possible mechanism.Methods]Human umbilical vein endothelial cells(HUVEC)were cultured in vitro for experiments with control group(5.5 mmol/L glucose)and intermittent high glucose group(5.5/28 mmol/L glucose).Intermittent high glucose simulating human blood glucose fluctuations was alternately cultured every 4 hours in the first 12 h and 5.5 mmol/L for another 12 h.According to this cycle,the cells were cultured for 48 h in total.Cell viability was measured by CCK-8,indicators related oxidative stress were detected by microplate reader,and detection of gene related autophagy by real-time fluorescent quantitative PCR.Results]Compared with the control group,intermittent high glucose group reduced cell viability,decreased intracellular antioxidant enzyme activity,increased the expression of malondialdehyde(MDA)and 8-Hydroxydeoxyguanosine(8-OHdG)(P<0.01),and increased the expression of Atg4 and Atg5 related autophagy(P<0.001).Conclusion]Fluctuant hyperglycemia may induce oxidative stress of HUVEC,thereby causing autophagy of HUVEC,ultimately to reduce cell viability.