Fig. 3.

Protective effect of metformin measured by the MTT assay. In the group receiving 1 mM metformin, metformin promoted slight cellular growth, showing maximal cell viability of 111.8% at the concentration of 1 mM metformin (no significant compared with control, P>0.05). Metformin provided significant protection (59.9%±3.7% for the gentamicin [GM] group vs. 75.6%±5% for the GM-plus-metformin group, mean±SE, n=5) against the toxic effect of 2.5 mM GM applied for 48 hours (^*P<0.05, compared with the GM group). Results from 5 separate experiments in triplicate.