Figure 2.

Demonstration of H₂O₂-mediated neurotoxicity and Nano-CAT-mediated protection. Primary human neurons were exposed to H₂O₂ (12.5–100 μM) for increasing time points (3–24 h). Metabolic activity was measured by MTT assay and expressed as a percentage of MTT activity (a, b). A dose- and time-dependent decrease in cell viability was observed (a, b). The cell membrane integrity was measured by LDH assay as fold increase over the respective control (c). Human neurons were exposed to H₂O₂ (50 μM) with or without Nano-CAT (50–200 μg/ml) or Nano-CON (200 μg/ml) (d) Cell survival was analyzed after 6 h by MTT assay as expressed as a percentage of MTT activity (d). Data are mean ±S.E.M. of a minimum of triplicates and representative of at least three biological replicates. Symbols indicate the relative level of significance compared with vehicle control (***P<0.001) or with the H₂O₂-treatment group (^ΩP<0.05 and ^ΩΩΩP<0.001) or with H₂O₂ alone (ns, not significant; ^###P<0.001)