Figure 2
Squalestatin alters the cellular distribution of Aβ 42 . (A) Concentrations of Aβ42 in detergent-resistant membranes (DRMs) (rafts) or detergent-soluble membranes (DSMs) 2 hours after the addition of conditioned media from 7PA2 cells (7PA2-CM) containing 10 nM Aβ42 to neurons pre-treated with control medium (■) or 200 nM squalestatin (□). Values are mean ± standard deviation (SD) from triplicate experiments performed three times (n = 9). (B) Cell extracts from neurons were separated on sucrose density gradients and analyzed by immunoblot for lysosome-associated membrane protein 1 (LAMP-1), a marker of lysosomes. (C) Immunoblot showing the amount of LAMP-1 in extracts from neurons treated with control medium or 200 nM squalestatin. (D) The amount of Aβ42 in lysosomes derived from neurons treated with control medium (□) or 200 nM squalestatin (□) and incubated with 7PA2-CM containing 10 nM Aβ42 for 2 hours. Values are mean ± SD from triplicate experiments performed three times (n = 9). *Concentrations of Aβ42 significantly higher (P <0.05) than controls.