FIGURE 3.

Protective effects of AO extracts on H₂O₂-induced toxicity in HT22 and Neuro-2a cells. Cells were exposed to various concentrations of H₂O₂ for different times in HT22 (A) and Neuro-2a cells, cell viability was measured by MTT assay (B). Cell viability of HT22 (C,D) and Neuro-2a cells (E,F), cell morphology of HT22 (G) and Neuro-2a (H) after treatment with different concentrations of AO extracts. Cell morphology was observed under microscope at 5× magnification. Samples were treated with AO extracts for 48 h and exposed to H₂O₂ (H200: 200 µM H₂O₂, H400: 400 µM H₂O₂) for 15 min to induce toxicity. The results are expressed as the means ± SEM of independent experiments (n = 3). ****p < 0.0001 compared to the untreated control; ^# p < 0.05, ^## p < 0.01, ^### p < 0.001 and ^#### p < 0.0001, compared to the group exposed to H₂O₂ only.