Effects of biodegradable Mg–6Zn alloy extracts on apoptosis of intestinal epithelial cells

In this study, intestinal epithelial cells (IEC)-6 were cultured in different concentration extracts of Mg–6Zn alloys for different time periods. To achieve a total of three concentrations (100%, 60% and 20% concentration), the extracts were serially diluted with Dulbecco's modified Eagle medium High Glucose to observe a dose–response relationship. We studied the indirect effects of Mg–6Zn alloys on IEC-6 cells apoptosis. The apoptosis of IEC-6 cells was measured using flow cytometry. And the apoptosis of IEC-6 cells was evaluated by investigating the expression of caspase-1and Bcl-2 using real-time polymerase chain reaction (PCR) and Western blotting tests. It was found that the levels of apoptosis in IEC-6 cells cultured in 100% Mg–6Zn alloy extracts were significantly higher than those in 60% and 20% extracts; the 100% extract can down-regulate expression of Bcl-2 after culture. The in vitro results indicated that the conspicuous alkaline environment and excessive Mg concentration, even Zn concentration caused by rapid corrosion of Mg–6Zn alloys promote IEC-6 cells apoptosis, although further experiments will be necessary to formally prove our conclusions. Therefore, the adjustment of the degradation rate is needed for using Mg–Zn alloy as a surgical suture material.

► We evaluated the effects of Mg–6Zn alloys on apoptosis of IEC-6 cells.
► The apoptosis was evaluated by investigating the expression of caspase-1 and Bcl-2.
► The IEC-6 cells displayed better cell functions in 60% or 20% extract.
► The conspicuous alkaline environment is disadvantageous to apoptosis of IEC cells.
► The excessive Mg concentration is disadvantageous to apoptosis of IEC-6 cells.