Figure 2.

Viability of primary ONHA cells after treatment with the investigated concentrations of minocycline (black curve, diamond) and additionally treated with 600 μM H₂O₂ (grey curve, triangles), measured by a colorimetric test (MTT). Tests were performed in triplicate and repeated three times. Untreated primary ONHA of the same passage served as the control. Results are expressed as the mean percentage of control cell survival. The data are the mean of results of three experiments, each performed in triplicate. Cells treated only with minocycline concentrations up to 40 μM showed no reduction in viability compared with the control, while 50 μM and higher showed a significantly reduced viability (P < 0.001). When cells were treated additionally with H₂O₂, those pretreated with minocycline > 15 μM (P = 0.02) up to 50 μM (P = 0.01) showed a significantly increased viability, with a peak at 20 μM (P < 0.001) compared with the control. Only concentrations as high as 150 μM showed significantly decreased viability (P < 0.001). Error bars, ± SD.

Abbreviations: ONHA; optic nerve head astrocytes; SD, standard deviation.