Figure 4.

The effect of matrine on apoptosis was determined by double staining with Annexin V-FITC/propidium iodide (PI) and flow cytometry. Fibroblast-like synoviocytes (FLS) were isolated from control or collagen-induced arthritis (CIA) rats, cultured in vitro, and treated with 0.75 mg/ml matrine, 25 µmol/l AG490, or a combination of matrine and AG490 for 24 h. (A) Representative FACS scatter plots for each drug treatment. Q1 indicates necrotic cells; Q2 indicates late apoptotic cells; Q3 indicates early apoptotic cells; and Q4 indicates living cells. (B) Cell apoptosis rates were analyzed via flow cytometry. Data are presented as mean ± SD of three independent experiments. ^**P<0.01 vs. the control group; ^##P<0.01 vs. the CIA group; ^ΔP<0.05 vs. the AG490 group.