Plasmalogens Inhibit APP Processing by Directly Affecting γ-Secretase Activity in Alzheimer’s Disease
Figure 3
Effect of PC-PL 18 : 1, PC-PL 20 : 4, PC-PL 22 : 6 and PE-PL 22 : 6 on β-secretase activity. (a) Influence on β-secretase activity in purified membranes of human SH-SY5Y cells. Purified membranes of SH-SY5Y cells were prepared, incubated with PC-PL 18 : 1, 20 : 4, 22 : 6, or PE-PL 22 : 6 and the corresponding phospholipids (100 μM), and β-secretase activity was determined by a fluorometric assay. A representative kinetic is shown for PC-PL 18 : 1 and PC 18 : 1. (b) Influence on β-secretase activity ex vivo in purified membranes of mouse brains. Purified membranes of mouse brains were incubated with PC-PL 18 : 1 and PC-PL 20 : 4 and the corresponding phospholipids PC 18 : 1 and PC 20 : 4 (100 μM). A representative kinetic is shown for PC-PL 18 : 1 and PC 18 : 1. (c) Living SH-SY5Y cells were incubated in cell culture with PC-PL 18 : 1 and PC-PL 20 : 4 and the corresponding phospholipids in a final concentration of 100 μM for 24 hours. After the incubation, purified membranes were prepared and analyzed in the β-secretase assay. A representative kinetic is shown for PC-PL 18 : 1 and PC 18 : 1. (a, b, c). All quantified data represent an average of at least three independent experiments. Illustration and statistical significance are as described for Figure 2.
