Aims: 

The significant but only modest improvements in clinical trials using stem cells after myocardial infarct have indicated the need of further development of cell-based therapies. Adipose derived stem cells (ASC) represent a new pool for autologous multipotent cells. Our aim was to quantify their potential on improving the survival of the injured cells in an in vitro ischemia reperfusion (I-R) model and to evaluate the mechanism of action.

Methods: 

H9c2 cardiomyoblasts were incubated in glucose free media and <3 mmHg oxygen. After the end of hypoxia experimental groups were treated with fluorescent labeled human ASCs or hASC conditioned media (ACM). Survival of postischemic cells was measured after 24 hours with flow cytometry using fluorescent viability stains and metabolic activity was estimated using PrestoBlue reagent.

Results: 

Using flow cytometry we found that in the I-R model without treatment the ratio of the living cells was 16.16±1.38% (mean±sem), while with hASC treatment this ratio significantly increased to 36.25±3.38% (p<0.001). Measurements on metabolic activity confirmed the positive effect of the hASC treatment and indicated that a less pronounced effect can be achieved with hASC conditioned medium only (I-R: 0.12±0.02; I-R+ASC: 0.31±0.03; I-R+ACM: 0.25±0.05; I-R vs. I-R+ASC: p<0.001, I-R vs. I-R+ACM: p<0.05).

Conclusion: 

The treatment with hASCs significantly increased the survival of the injured cells and this effect was attained partially via paracrine factors. These results support the use of ASCs as an autologous cell source for cell-based therapies.

Support: 

TÉT-SIN, TÁMOP 4.2.2-08/1/KMR-2008-0004, TÁMOP-4.2.1/B 09/1/KMR-2010-0001, OTKA 83803, Bolyai fellowship