Figure 8. No effect of siramesine on cathepsin activity in cell lysates from human lens epithelial cells (HLEC). The enzymatic activity measured in cell lysates with final concentrations of siramesine between 0 and 30 µM at a pH of 5.5. Leupeptin (50 µM), a known Cathepsin B inhibitor, was used as a negative control and displayed a significant drop in activity. The diagram shows V_max at each concentration of siramesine where n=3. Mean±SEM is shown. p<0.001 (***). The experiment was repeated twice with similar results.