FIG. 8.

Cytotoxicity of ART on RAW264.7 cells. After overnight culture in a 96-well culture plate, cells (10⁴ cells/well in DMEM) were washed and incubated with various concentrations of ART for 6 or 24 h. Subsequently, 20 μl of MTT solution (5 mg/ml in PBS) were added in a total volume of 200 μl of medium. Cells were incubated for 4 h at 37°C and 5% CO₂; the supernatant was then removed, and 150 μl of DMSO was added to each well to dissolve the produced formazan crystals. The extinction was measured at 490 nm by using a microplate reader. *, P < 0.05; **, P < 0.01 versus medium only group. The datum points are presented as means ± the standard deviation. The experiment was repeated three times. OD₄₅₀, optical density at 450 nm.