5-氮杂胞苷诱导小鼠骨髓间充质干细胞分化过程中PPARγ表达及其作用

PPARγ expression and its effects on the differentiation of mesenchymal stem cells induced by 5-Azacytidine in vitro

目的 探讨 5 氮杂胞苷诱导骨髓间充质干细胞 (MSC)分化过程中PPARγ的表达情况及其在细胞分化过程中的作用。方法 利用原代培养小鼠MSC ,5 氮杂胞苷诱导分化 ;脂质体转染法 ,将pEGFP N1 PPARγ2表达质粒转入MSC中 ,G418筛选 ,RT PCR检测PPARγmRNA表达 ,免疫组化检测myosin及PPARγ表达。油红O染色检测细胞内脂滴。结果 MSC在未诱导时不表达PPARγ ,经 5 氮杂胞苷诱导后 ,多数细胞向成肌细胞分化 ,部分细胞表达PPARγ且向成脂肪细胞分化 ;pEGFP N1 PPARγ2转染成功的细胞均分化为脂肪细胞。结论 5 氮杂胞苷不仅诱导MSC向成肌细胞分化 ,也诱导其向成脂肪细胞分化 ;其诱导MSC向成脂肪细胞分化可能与PPARγ表达有关。

Objective To explore the expression of peroxisome proliferator activated receptorγ (PPARγ) and its roles in the differentiation of mesenchymal stem cells (MSCs) induced by 5 Azacytidine. Methods 5 Azacytidine was used to induce the differentiation of primary cultured mesenchymal stem cells. The eukaryotic expression plasmid vector pEGFP N1 PPARγ was transfected into MSCs with lipotransfection method followed by G418 selection. The expression levels of PPARγ mRNA were detected by RT PCR. Immunohistochemistry and Western blot were employed to study the protein expression of PPARγ. Lipid droplets in the cells were stained with Oil Red O. Results No expression of PPARγ mRNA was found in undifferentiated MSCs. After induction by 5 Azacytidine, partial MSCs expressed PPARγ and differentiated into lipoblasts. MSCs, transfected with pEGFP N1 PPARγ2, differentiated into adipocytes. Conclusion 5 Azacytidine can induce the differentiation of MSCs into myoblasts and lipoblasts, which may be related to the expression of PPARγ.