不同浓度5-氮胞苷体外诱导人脐带间充质干细胞向心肌样细胞的分化

背景:在体外将人脐带间充质干细胞诱导为心肌样细胞的5-氮胞苷合适浓度的研究较少,且无明确结论。目的:对比不同浓度5-氮胞苷诱导人脐带间充质干细胞转化为心肌细胞的效果,以确定一种合适的诱导浓度。方法:第2代人脐带间充质干细胞中分别加入浓度为2.5,5,10,20,40,80μmol/L的5-氮胞苷,作用24h后除去,继续培养4周。于诱导后第2周行免疫组化染色检测肌钙蛋白Ⅰ阳性细胞率。结果与结论:5-氮胞苷诱导后7d,细胞形态发生变化,细胞多紧密平行排列生长,细胞体积变大,梭形细胞比例下降,40,80μmol/L组细胞形态变化明显。4周时,40,80μmol/L组细胞的折光性减低,细胞活性减弱,继续出现死亡的细胞。诱导后2周,2.5μmol/L组肌钙蛋白Ⅰ染色为阴性,10,20,40,80μmol/L组细胞肌钙蛋白Ⅰ阳性率均明显高于5μmol/L组(P<0.05)。提示5-氮胞苷可诱导人脐带间充质干细胞向心肌样细胞转化,10μmol/L是较佳的诱导浓度。

5-azacytidine induced differentiation of human umbilical cord mesenchymal stem cells into cardiomyocytes in vitro

BACKGROUND: Studies addressing the induced effect of different-concentration 5-azacytidine on the in vitro differentiation of human umbilical cord mesenchymal stem cells (hUC-MSCs) into cardiomyocytes are fewer. OBJECTIVE: To select a suitable concentration of 5-azacytidine to induce differentiatiown of hUC-MSCs into cardiomyocytes in vitro. METHODS: Second passage hUC-MSCs were cultured in culture medium containing different -concentration 5-azacytidine (2.5, 5, 10, 20, 40, 80 μmol/L, respectively). After incubating for 24 hours, the medium was changed to complete medium without 5-azacytidine. Thereafter, the cells were cultivated for 4 weeks. Two weeks after the cells were treated with 5-azacytidine, cardiac troponin Ⅰ was assayed by immunohistochemical methods and the ratio of positive cells for cardiac troponin Ⅰ was counted. RESULTS AND CONCLUSION: Seven days after hUC-MSCs were treated with 5-azacytidine, the cellular morphology began to change. The cells arranged closely and in parallel. The cellular morphology of 40 and 80 μmol/L groups changed obviously. At 4 weeks, the refraction and activity of cultured cells declined in the 40 and 80 μmol/L groups, and some of the cells died. At 2 weeks, cardiac troponin Ⅰ was positive for hUC-MSCs in 5, 10, 20, 40 and 80 μmol/L groups and negative in 2.5 μmol/L and control groups. The ratio of positive cells for cardiac troponin Ⅰ in 10, 20, 40 and 80 μmol/L groups was significantly higher than that of 5 μmol/L group (P < 0.05). l0 μmol/L 5-azacytidine is the optimal concentration for hUC-MSCs differentiation into cardiomyoctyes.