Expressions of Bcl-2 and Bax and apoptotic rate of bone marrow mesenchymal stem cells transfected with thymosin beta4 in a hypoxic environment

doi:10.3969/j.issn.2095-4344.2014.41.003

Abstract

Abstract:

BACKGROUND: Studies have shown that thymosin β4 can improve the anti-apoptotic ability of a variety of cells, but the reports describing the changes in the anti-apoptotic ability of bone mesenchymal stem cells modified with thymosin β4 gene in the hypoxic environment are rare.

OBJECTIVE: To observe the change in the apoptotic rate of bone mesenchymal stem cells modified with thymosin β4 gene in the hypoxic environment, and to explore whether thymosin β4 affects the apoptosis of bone marrow mesenchymal stem cells via regulating the expression of Bax and Bcl-2.

METHODS: Bone marrow mesenchymal stem cells were transfected with the recombinant lentiviral vector over-expressing the thymosin β4 gene, and then we observed the expression of thymosin β4 using western blot assay. Cells were divided into three groups: thymosin β4 transfection group, control virus group, and untreated group. All three groups were placed in a hypoxic environment. The apoptotic rate of bone marrow mesenchymal stem cells was evaluated by the flow cytometry assay. The expression of Bax and Bcl-2 protein was detected by western blot.

RESULTS AND CONCLUSION: Thymosin β4 gene was expressed successfully in the bone marrow mesenchymal stem cells showed by the western blot. The apoptotic rate of bone marrow mesenchymal stem cells in the hypoxic environment was lower in the thymosin β4 transfection group than the control virus group and untreated group; while there was no difference between the latter two groups. Western blot results showed that the expression of Bcl-2 protein was higher in the thymosin β4 transfection group than the control virus group and untreated group, and the expression of Bax protein was lower in the thymosin β4 transfection group than the control virus group and untreated group. No difference in the expression of Bax and Bcl-2 was found between the control virus group and untreated group. These findings indicate that thymosin β4 overexpression can improve the anti-apoptotic ability of bone mesenchymal stem cells modified in the hypoxic environment, and its possible mechanism is through regulating the expression of Bax and Bcl-2 protein.

中国组织工程研究杂志出版内容重点：干细胞；骨髓干细胞；造血干细胞；脂肪干细胞；肿瘤干细胞；胚胎干细胞；脐带脐血干细胞；干细胞诱导；干细胞分化；组织工程

全文链接：

Key words: stem cells, mesenchymal stem cells, thymosin, apoptosis

CLC Number:

R394.2

Liu De-sheng, Xiao Shi-liang, Wang Bo, Zhou Cheng. Expressions of Bcl-2 and Bax and apoptotic rate of bone marrow mesenchymal stem cells transfected with thymosin beta4 in a hypoxic environment[J]. Chinese Journal of Tissue Engineering Research, 2014, 18(41): 6573-6577.

Figures/Tables 2

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