Figure 5.

Influence of cholesterol depletion on the secretion of APPsα, APPsβ, and Aβ from human astroglioma (U373) cells. U373 cells were incubated for 30 min with 10 mM MβCD for cholesterol depletion. After 4 h incubation, medium was collected, and quantitative analysis of secreted APPsα and APPsβ was performed as described in Materials and Methods. For Aβ detection, a highly specific ELISA assay was performed. The results are expressed as percentage of secreted APP fragments in control HEK cells and are the averages ± SD of at least four experiments. Statistical significance between control cells and MβCD-treated cells was determined by Student's unpaired t test (**, P < 0.001).