Flow cytometry analysis with annexin V–FITC/PI double
staining showed that acrolein 50 mM increased apoptosis and
necrosis in HMEECs. Cells were incubated in the absence of
acrolein for 24 h (control) or in the presence of 10 mM acrolein for
24 h and 50 mM acrolein for 24 h. Undamaged cells were stained
with negative annexin V–FITC/PI (bottom left quadrant). After
incubation with 50 mM acrolein for 24 h, circa three-fold more
apoptotic cells compared to controls were stained positively with
annexin V–FITC and negatively with PI (bottom right quadrant),
and advanced apoptotic cells were stained by annexin V–FITC and
PI (upper right quadrant). At 100 mM acrolein, the cells were no
longer viable (Fig. 2).
The loss of viability of HMEECs was determined by evaluating
the nuclear morphology using Hoechst 33342 staining. The nuclei
of normal control cells were round with homogeneous intensity
(Fig. 3A). However, addition of 50 mM acrolein resulted in nuclei