Zeaxanthin Inhibits Hypoxia-Induced VEGF Secretion by RPE Cells through Decreased Protein Levels of Hypoxia-Inducible Factors-1α

Figure 6

Effect of hypoxia on HIF-1α protein levels in RPE cells. RPE cells were seeded into 6 cm culture dishes at a density of cells per well. After 24 h, cells were incubated in a controlled environment of 1% O₂ (a) or added with CoCl₂ (b) at 50, 100, 150, and 200μM. Cells cultured under normoxic condition and without CoCl₂ served as normal controls. Cells were collected 24 h later; HIF-1α protein levels in cell extracts were determined by using the Intracellular HIF-1α ELISA kits and expressed as percentages of the control (, ). Hypoxia significantly increased HIF-1α protein levels in RPE cells. , compared with the controls.

(a)

(b)