Figure 2. Inhibition of VEGFR-2 activation activity of VEGF by
EGCG is retained after removal of unbound polyphenol using a
dialysis membrane. HUVECs were treated for 5 min with preincubated
basal medium containing 25 ng/mL VEGF, 25 ng/mL
VEGF and 1 M EGCG, or samples prepared by dialysis (including
the controls). For the dialysed samples, VEGF was incubated
with or without EGCG for 30 min at room temperature prior to
dialysis for 2 or 24 h at 4C. The controls were incubated in the
same conditions without dialysis. The retentate was diluted in
medium to give a final concentration of 25 ng/mL VEGF and 1 M
EGCG. Phosphorylated VEGFR-2 was determined by ELISA. *p <
0.05, **p < 0.01, ***p < 0.001 compared to their stimulated cells,
respectively. Data expressed as mean ± SD (n = 3).