Figure 3.

Cell viability and morphology of rat primary cortical neurons after treatment with CuCl₂ and Hcy in the absence or presence of Aβ42. Aggregations for viability and morphology studies were performed identically to previous aggregation assays, but lacking ThT due to its cytotoxicity. After 4 h agitation, samples were subsequently collected for the assessments. (A) Primary neurons were incubated for 72 h with increasing μM concentrations of CuCl₂ (dark gray), CuCl₂ + Hcy (light gray), or Hcy (stripes) without Aβ42, to study their individual cytotoxicity. Control sample (aggregation assay reaction mixture) is visualized in the white column. (B) Effect of CuCl₂ and Hcy on Aβ42-induced toxicity. 5 μM Aβ42; 5 μM Aβ42 + 5 μM CuCl₂; 5 μM Aβ42 + 5 μM CuCl₂ + 50 μM Hcy; 5 μM Aβ42 + 50 μM Hcy were incubated on the cells for 72 h. As controls non-fibrillar 5 μM Aβ42 (MonoAb) and aggregation assay reaction mixture without Aβ42 were used. All values are relative to reaction mixture control sample ± S.D. (C) Immunofluorescent staining of primary cortical neurons after 24 h incubation. Antibody against neuronal marker, MAP2 (green), visualizes the changes of neuronal morphology; whereas anti-human APP (red) shows the Aβ aggregates and DAPI (blue) the cell nuclei. Concentrations were as indicated in (B). Scale bar represents 100 μm.