Figure 6. Berberine taken orally by diabetic patients inhibited leukocyte-mediated apoptosis of human retinal endothelial cells (HRECs; A and B) and decreased integrin beta-2 (CD18) expression on neutrophils (C and D). A and B show representative dot plots of leukocyte-mediated death of HRECs before and after berberine treatment. The data in C are expressed as cell counts (y-axis) plotted as a function of fluorescence intensity (x-axis), and show CD18 expression and leukocyte-mediated killing of HRECs before and after the 1 month treatment with berberine. Plots shown are representative of independent experiments in each group. Results in the histogram of CD18 expression (D) are normalized to the immunoglobulin (IgG) isotype control. * Leukocyte-mediated killing of HRECs after berberine is p<0.05 compared to the same measurement before berberine treatment. N=28.