Page 121 - Magnesium-based supports for stem cell therapy of vascular disease - Mónica Echeverry Rendón

ENDOTHELIAL FUNCTION AFTER EXPOSITION OF MAGNESIUM DEGRADATION PRODUCTS
However, the addition of extracts of c.p.Mg rapidly and consistently decreased resistance, indicating a complete loss of endothelial interconnectivity. Extracts from the coated Mg decreased transendothelial resistance to a lesser extent, however, although some recovery was observed, the cells did not return to baseline resistance and had a decrease in resistance close to 50%.
Fig.5. Paracellular permeability of HUVECs monolayer after addition of Mg extracts. Measurement of electric resistance of monolayer of HUVECs was carried out by using ECIS method. A decrease of around a 50% in the permeability of cells treated with HMT and MAN extracts was observed. On the other side cells treated with c.p Mg died after around 2 h.
3.5 Monolayer integrity for HUVEC to Mg extracts
In order to confirm the results obtained through the ECIS measurement, cells were recorded during and after the addition of the extracts. In Fig.6 the most representative changes are showing. This information confirms what was previously observed, cells are reacting to the change of the medium. For controls a temporary breach of monolayer was observed however cells returned to the previous stage after 3 h. Monolayer treated with c.p Mg had a rapid destruction and cell death process was clearly observed after about 2 h. On the other hand, after the addition of HMT and MAN extracts to the cells, it was observed slight changes in the configuration of the monolayers but fully recovered after 6h.
3.6 Vascular reactivity study
The vasoreactivity of the RCA to Bradykinin-induced vasorelaxation was investigated in RCA-rings exposed to Mg extracts. Control rings show a vasorelaxation response which is elevated by increasing dosages of Bradykinin (fig.7). In contrast, RCA-rings pretreated with extracts from c.p Mg showed a significant decrease in their response to Bra- dykinin, indicating a loss of endothelial-dependent vasorelaxation. RCA rings exposed to extracts from the HMT ot MAN-coated Mg did not lose their vasorelaxation capacity and did not differ from control rings.
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