Figure 4

Cu²⁺ and Cu-chelators modulate the aggregation state of intracellular Aβwt in transgenic C. elegans. A. The white rectangle on the DIC image of a C. elegans hermaphrodite (top picture) indicates the region of the worm where all quantifications were done (the same region, stained with ThS in seen below). * Indicates the position of the pharyngeal bulb. B. Morphology of ThS-positive amyloid deposits formed in the presence of Cu²⁺ and Cu-chelators. Images correspond to C. elegans grown on regular NGM agar plates (a), treated with 150 μM CuCl₂ (b), 150 μM histidine (c) or 150 μM clioquinol (d) for 144 h. The amyloid deposits were stained with ThS and photographed under an epifluorescence microscope. Arrows indicate ThS positive amyloid aggregates. The images are representative of 4 experiments where 40 worms were analyzed for each treatment. Bar 20 μm. C. The graph represents the number of aggregates formed anterior to the pharyngeal bulb at different times (48–144 h) under control conditions (white bars) and when the animals were treated with CuCl₂ (150 μM, black bars), histidine (150 μM, dark grey bars), or clioquinol (150 μM, pale gray bars). Bars indicate standard error, **p < 0.01; ***p < 0.001. D. The graph shows the digital quantification (Sigma Scan Pro 5) of the ThS-positive amyloid deposits present anterior to the pharyngeal bulb. The graph represents the total area of aggregates formed anterior to the pharyngeal bulb at different times (96–144 h) under control conditions (white bars) and when the animals were cultured in the presence of CuCl₂ (150 μM, black bars), histidine (150 μM, dark grey bars), or clioquinol (150 μM, pale gray bars). Bars indicate standard error, *p < 0.05; **p < 0.01; ***p < 0.001. The p values indicate differences between a given treatment and the control..