FIGURE 6.

N1 protects primary cultured mouse cortical neurons from Aβ oligomer-induced toxicity and cell death. A, primary cultured mouse cortical neurons (seeded on 96-well plates) were treated (24 h) with recombinant N1, N2 (1 μm), or an equivalent volume of control buffer (Ct) with Αβ oligomer-enriched conditioned media (4-fold dilution). Twenty-four hours after incubation, cells were treated as above for an additional 24-h period, and then neuronal viability was determined by 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide assay as described under “Materials and Methods.” Values are the means of three independent experiments (carried out in triplicates) and are expressed as percentage of control untreated cells (taken as 100). Error bars = S.E. B, representative pictures of mouse primary cultured neurons seeded on glass coverslips treated as in A and then processed for TUNEL as describe under “Materials and Methods.” C, TUNEL-positive nuclei were counted in six independent optical fields. Bars correspond to the percentage of labeled nuclei of total DAPI-stained nuclei. *, p < 0.05; **, p < 0.01.; ns, not statistically significant.