Abstract
Background:
Contributing factors for improved survival of human adipocytes mesenchymal stem cells (h-AMSCs) cultured through hypoxia preconditioning, in example apoptosis inhibition involving BCL2 and HSP27 expression, trigger signal expression (VEGF), SCF expression, OCT-4 expression, and CD44+ expression. The objective if this study was to explain the mechanism and role of hypoxic preconditioning and the optimal duration of hypoxic preconditioning exposure to improve survival of h-AMSCs. Methods:
: An experimental laboratory explorative study ( in vitro ) with hypoxic preconditioning in h-AMSCs cultures. This research was conducted through four stages. First, isolation of h-AMSCs culture from adipose tissue of patients. Second, the characterization of h-AMSCs from adipose tissue by phenotype (flowcytometry) through CD44+, CD90+ and CD45-expression before being pre-conditioned for hypoxic treatment. Third, the hypoxic preconditioning in h-AMSCs culture ( in vitro ) was performed with an oxygen concentration of 1% for 24, 48 and 72 hours. Fourth, observation of survival from h-AMSCs culture was tested on the role of CD44+, VEGF, SCF, OCT-4, BCL2, HSP27 with Flowcytometry and apoptotic inhibition by Tunnel Assay method. Results:
: The result of regression test showed that time difference had an effect on VEGF expression ( p <0.001; β =-0.482) and hypoxia condition also influenced VEGF expression ( p <0.001; β =0.774). The result of path analysis showed that SCF had effect on OCT-4 expression ( p <0.001; β =0.985). The regression test results showed that time effects on HSP27 expression ( p <0.001; β =0.398) and hypoxia precondition also affects HSP27 expression ( p <0.001; β =0.847). Pathway analysis showed that BCL2 expression inhibited apoptosis ( p =0.030; β =-0.442) and HSP27 expression also inhibited apoptosis ( p <0,001; β =-0.487). Conclusion:
Hypoxic preconditioning of h-AMSC culture has proven to increase the expression of VEGF, SCF, OCT-4, and BCL2 and HSP27. This study demonstrated and explained the existence of a new mechanism of increased h-AMSC survival in cultures with hypoxic preconditioning (O2 1%) via VEGF, SCF, OCT-4, BCL2, and HSP 27.