同型半胱氨酸干扰胰岛素样生长因子2和H19的印迹表达及其与血管平滑肌细胞增殖的关系

Homocysteine Harass the Imprinting Expression of Insulin-Like Growth Factor-2 and H19 and Its Correlation with the Proliferation of Vascular Smooth Muscle Cells

目的采用动脉粥样硬化的独立危险因子同型半胱氨酸刺激脐静脉血管平滑肌细胞,观察同型半胱氨酸对血管平滑肌细胞胰岛素样生长因子2和H19表达的干扰作用,分析二者与血管平滑肌细胞增殖的关系及其在动脉粥样硬化发病中的可能作用。方法将培养的脐静脉血管平滑肌细胞分为0、50、100、200、500及1000μmol/L同型半胱氨酸组,以0μmol/L同型半胱氨酸组为空白对照组。用不同浓度的同型半胱氨酸刺激血管平滑肌细胞48 h后,MTT法检测血管平滑肌细胞的增殖水平;半定量逆转录聚合酶链反应法检测血管平滑肌细胞胰岛素样生长因子2和H19的mRNA表达水平,Western Blotting法检测血管平滑肌细胞胰岛素样生长因子2的蛋白表达水平。结果与空白对照组相比较,同型半胱氨酸各浓度组血管平滑肌细胞的增殖活力明显增加,以高浓度(500及1 000μmol/L)组为著(P<0.05)。同时,同型半胱氨酸组血管平滑肌细胞H19的mRNA表达水平增加,500及1000μmol/L浓度组(0.548 6±0.063 3及0.733 3±0.049 6)明显高于空白对照组(0.202 2±0.012 4)(P<0.05);胰岛素样生长因子2的mRNA和蛋白表达均下降,尤以高浓度组为著,500及1 000μmol/L浓度组的mRNA(0.258 8±0.024 8及0.168 9±0.069 6)和蛋白(0.116 7±0.015 5及0.083 7±0.018 0)表达水平均明显低于空白对照组(0.515 8±0.018 9和0.244 3±0.042 3)(P<0.05)。结论同型半胱氨酸能干扰胰岛素样生长因子2和H19的表达,并可能进一步促进血管平滑肌细胞的增殖。

Aim To investigate the potential impact of homocysteine（Hcy） on the expression of insulin-like growth factor-2（IGF-2） and H19 in vascular smooth muscle cells（VSMC）,analyze its possible correlation with the proliferation of VSMC and its role in the pathogenesis of atherosclerosis（As）. Methods Cultured human umbilical VSMC were divided into 0,50,100,200,500,1000 μmol/L Hcy group,and the 0 μmol/L Hcy group was the control.After the VSMC were treated with different concentrations of Hcy for 48 h,the cell viability was detected by MTT,the mRNA levels of H19 and IGF-2 were determined by reverse transcription polymerase chain reaction,and the protein expression of IGF-2 by Western Blotting. Results Compared with the 0 μmol/L Hcy groups,the viability of VSMC was increased in the Hcy groups,especially in 500 and 1000 μmol/L Hcy groups（P0.05）.The H19 expression of VSMC in Hcy groups was increased,and its levels in the 500 and 1000 μmol/L group（0.548 6±0.063 3 and 0.733 3±0.049 6）were significantly higher than that in the 0 μmol/L Hcy group（0.202 2±0.012 4）（P0.05）,while the IGF-2 mRNA and protein was down-expressed,which were also more significant in the 500 and 1 000 μmol/L group（mRNA： 0.258 8±0.024 8 and 0.168 9±0.069 6 vs 0.515 8±0.018 9,P0.05;protein： 0.116 7± 0.015 5 and 0.083 7±0.018 0 vs 0.244 3±0.042 3,P0.05）. Conclusion Hcy harassesd the imprinting expression of IGF-2 and H19 in the VSMC.The expression of H19 was increased and that of IGF-2 decreased.The aberrant expression of IGF-2 and H19 possibly induced the proliferation of VSMC.