Figure 2. Effect of proteinase inhibitors on the degradation of MBP by lysates or supernatants.

30 µl of lysates (A) or 50 µl of supernatants (B) from LPS-activated astrocytes were incubated for 24 h at 37°C with 10 µg of exogenous MBP in the presence of CaCl₂ (10 mM) and: 20 µM E-64; 2 mM PMSF; 10 mM IA; 2 mM EDTA; 4 mM PA or a pool containing all the inhibitors at the used concentrations. The positive control (LPS) is represented by MBP incubated with lysates or supernatants from LPS-activated astrocytes in the absence of inhibitors. Histograms show the percentage of non-degraded MBP compared to negative control (MBP control), represented by MBP incubated in the same experimental conditions without cell culture supernatant or lysate. Results represent the mean ± SD of three separate experiments using lysates or supernatants from different cell populations. Statistically significant inhibition of MBP degradation in comparison to that of positive control is indicated with * (One way ANOVA followed by Student – Newman – Keuls post hoc test; * =  p<0.05).