西格列汀及胰高血糖素样肽1对脐静脉内皮细胞铁代谢相关基因的调控作用

Effects of sitagliptin and glucagon like peptide-1 on the regulations of genes involved in iron metabolism in human umbilical vein endothelial cells

目的 观察西格列汀及胰高血糖素样肽1（GLP-1）对正常糖浓度（正糖）及高糖条件下人脐静脉内皮细胞（HUVECs）铁代谢相关共济蛋白（FXN）及顺乌头酸梅1（ACO1）蛋白表达的影响.方法 用西格列汀（1μmol/L）和（或）GLP-1（100 nmol/L）处理HUVECs,正糖（5.5 mmol/L）及高糖（30.0 mmol/L）状态下分别设相应对照组、GLP-1处理组、西格列汀处理组以及GLP-1＋西格列汀联合处理组.检测药物对正常状态下HUVECs细胞增殖的影响,用实时定量逆转录PCR和Western blotting法分别于24 h及48 h后检测HUVECs内FXN和ACO1的mRNA及蛋白表达水平.多组间比较采用单因素方差分析,两组间比较使用Bonferroni检验（满足方差齐性检验时）或Dunnett T3检验（不满足方差齐性检验时）.结果 （1）正糖下经西格列汀和（或）GLP-1处理24 h后,与对照组（表达水平设为1）相比,各组的HUVECs细胞增殖水平均无明显变化（分别为0.99±0.04、1.07±0.08、1.06±0.05,F=4.059,均P〉0.05）;而各加药组的FXN mRNA表达均呈下降趋势,其中,西格列汀＋GLP-1组FXN的mRNA表达水平降低为0.68±0.18（t=3.59,P〈0.05）;西格列汀单独或联合GLP-1组ACO1的mRNA表达水平也明显降低（分别为0.49±0.13、0.59±0.15,F=10.802,均P〈0.05）;各加药组的FXN及ACO1的蛋白水平均低于对照组,但差异无统计学意义（均P〉0.05）.（2）高糖下经西格列汀和（或）GLP-1处理48 h后,与对照组（表达水平设为1）相比,西格列汀＋GLP-1组FXN mRNA表达升高（1.75±0.26,t=-5.71,P〈0.05）;但各组的ACO1 mRNA表达变化均不明显且差异无统计学意义（均P〉0.05）.结论 西格列汀和GLP-1可在不影响正常状态内皮细胞增殖的条件下,通过调节正常或高糖状态下HUVECs中FXN及ACO1的表达水平影响细胞内的铁代谢.

Objective To investigate the effects of sitagliptin and glucagon like peptide-1 （GLP-1） on the iron metabolism in human umbilical vein endothelial cells （HUVECs） under normal and high glucose conditions. Methods HUVECs were treated with sitagliptin （1μmol/L） and/or GLP-1 （100 nmol/L） under normal （5.5 mmol/L） and high glucose （30.0 mmol/L） conditions, and the corresponding control groups were also included. Cell viability was evaluated. After treatment for 24 h in normal glucose and 48 h in high glucose, mRNA and protein expressions of frataxin （FXN） and aconitase1 （ACO1） were measured by real-time PCR and Western blotting, respectively. Multiple-group comparisons were performed using one-way variance analysis.The two groups were compared using the Bonferroni test （when the variance homogeneity test was performed） or the Dunnett T3 test （when the variance homogeneity test was not satisfied）. Results （1） Comparing with the control group （assuming its expression level was 1） under normal glucose condition, cell viability had no significance among those groups treated with GLP-1, sitagliptin and the combinations of sitagliptin and GLP-1 （0.99±0.04, 1.07±0.08, 1.06±0.05,F=4.059, all P〉0.05）;mRNA expressions of FXN were significantly decreased by combinations of sitagliptin and GLP-1 administration （0.68 ± 0.18, t=3.59, P〈0.05） and mRNA expressions of ACO1 were significantly decreased by sitagliptin with or without GLP-1 treatment （0.59 ± 0.15, 0.49 ± 0.13, F=10.802, all P〈0.05）;While protein expressions of FXN and ACO1 were decreased by sitagliptin and/or GLP-1 with no significance （all P〉0.05）. （2） Comparing with the control group （assuming its expression level was 1） under high glucose condition, mRNA expressions of FXN were significantly increased by combinations of sitagliptin and GLP-1 administration （1.75 ± 0.26, t=-5.71, P〈0.05）, while mRNA expressions of ACO1 showed no much significance after treatment with sitagliptin and/or GLP-1. Conclusions Without affecting cell proliferation in normal state of endothelial conditions,sitagliptin and GLP-1 may affect the intracellular iron metabolism by regulating the expression of FXN and ACO1 in HUVECs in normal or hyperglycemic conditions.