同型半胱氨酸对心肌细胞质量及蛋白质合成的影响

Influence of homocysteine on cardiomyocyte hypertrophy in cultured cardiac myocytes

目的探讨同型半胱氨酸对心肌细胞肥大和蛋白质合成的影响。方法以培养的SD乳鼠心肌细胞为实验模型,以心肌细胞蛋白含量、表面积和蛋白合成速率作为心肌细胞肥大的指标,探讨同型半胱氨酸对上述指标的影响。结果与对照组相比,经同型半胱氨酸作用后,单个心肌细胞蛋白质含量实验组显著高于对照组,在三组实验组中,随着同型半胱氨酸浓度升高,单个心肌细胞质量也随之增加。实验组单个心肌细胞表面积显著高于对照组,不同浓度的同型半胱氨酸对心肌细胞表面积的影响也具有显著性差异。以[3H]-Leu掺入量来评价同型半胱氨酸对心肌细胞蛋白合成速率的影响,用同型半胱氨酸作用6h后的心肌细胞[3H]-Leu掺入量显著高于对照组。结论同型半胱氨酸在培养的心肌细胞中能促进蛋白质的合成,导致心肌细胞质量增加和细胞表面积增加,从而导致心肌细胞肥大。

Objective：To explore the influence of homocysteine on cardiomyocyte hypertrophy and protein synthesis in cultured cardiac myocytes.Methods：Myocardial cells from neonate rats were cultured in vitro and the influence of homocysteine on cell protein content,cell surface area and -Leucine（-Leu） incorporation in cultured cells were assessed.Results：The total cell protein content was stimulated by homocysteine in the cultured cardiomyocytes compared with control group.The higher level of homocysteine could increase the content of total cell protein The homocysteine increased cell surface area in a dose dependent manner.After 0.1mmol/L,0.5 mmol/L and 1.0 mmol/ L of homocysteine were added,the cell surface areas were 1452±499 μm2,1958±469 μm2,and 2196±502 μm2,respectively,significantly higher than the surface area of the control（P0.01）.To assess the protein synthesis rate of cultured cardiomyocytes,the-Leu incorporation was measured after different levels of homocysteine were added.The homocysteine increased the-Leu incorporation also in a dose dependent manner.Conclusions：Homocysteine could expedite the protein synthesis in cultured cardiomyocytes and lead to increase of the mass and cell surface area of cardiomyocytes.