Methionine sulfoxide reductase A: Structure, function and role in ocular pathology

Figure 3 Regulation of methionine sulfoxide reductase A and B2 in retinal pigment epithelial subjected to chemically induced hypoxia. Hypoxia-inducible factor (HIF)-1α (A) and vascular endothelial growth factor (VEGF) (B and C) were used to validate hypoxia from CoCl₂. Confluent human fetal retinal pigment epithelial (RPE) cells were serum starved overnight and treated with 100 μmol/L CoCl₂ for 4 h. Western blot analysis shows HIF-1α (mouse monoclonal, Novus Biologicals) upregulation in nuclear extracts of CoCl₂-treated RPE cells (A). VEGF expression was significantly upregulated both at the mRNA (B) and protein levels (C). Real-time polymerase chain reaction was performed as described[19] in a light cycler (Roche, IN, USA) using β-actin as normalizing gene. A polyclonal antibody (Santa Cruz Biotechnology, Santa Cruz, CA, USA) was used for the detection of VEGF. Methionine sulfoxide reductase (Msr) A and MsrB showed initial upregulation but, at 4 h, showed significant downregulation (D and E). Data presented are mean ± SE. ^aP < 0.05 vs control.