Figure 6.

The cytotoxicity in the presence or absence of N-acetylcysteine (NAC). EMT-6 cells were incubated with 1 μM artesunate (ART) for 24 h, and then with 1 mM 5-aminolevulinic acid (5-ALA) for a further 4 h in the presence (+) or absence (−) of 15 mM NAC. After rinsing with fresh medium, the cells were exposed to ultrasound (US). Cells were sonicated for 60 s at a frequency of 3 MHz and a power intensity of 3 W/cm², and a 20% duty cycle was used. Subsequently, the cells were re-incubated at 37 °C for 4 h in the dark. Following incubation, the cells were harvested and prepared for cell analysis. (A) The percentage of reactive oxygen species (ROS)-positive cells (%); (B) The percentage of apoptotic cells; (C) The cell viability (%). ** p < 0.01: ART + 5-ALA + US group vs. Control. Results are presented as the mean ± standard deviation.