Figure 4.

NAS inhibits the dissipation of ΔΨ_m of HepG2 cells induced by H₂O₂. (A) (a, b, c): ΔΨ_m observed with rhodamine 123 staining under fluorescence microscopy. (B) (d, e, f) Morphologic changes in nuclei observed under the inverted phase contrast microscope. (a, d) Untreated group; (b, e) H₂O₂ group, HepG2 cells incubated with 200 μM H₂O₂ for 6 hours; (c, f) H₂O₂ + NAS group, 10 μM NAS was administered before subjecting to H₂O₂. (C) ΔΨ_m detected by flow cytometry after TMRM staining. Note that untreated group cells display a granular pattern of TMRM fluorescence in cytoplasm; H₂O₂-treated cells showed diffuse pattern of TMRM fluorescence, indicating apoptotic nuclei; the dissipation of ΔΨ_m was almost completely abrogated by pretreatment with NAS. The arrows indicate the apoptotic cell. Original magnification ×400.