Albumin suppresses vascular endothelial growth factor via alteration of hypoxia-inducible factor/hypoxia-responsive element pathway

作者：Katavetin Pisut; Inagi Reiko; Miyata Toshio; Tanaka Tetsuhiro; Sassa Ryoji; Ingelfinger Julie R; Fujita Toshiro; Nangaku Masaomi^*

来源：Biochemical and Biophysical Research Communications, 2008, 367(2): 305-310.

DOI：10.1016/j.bbrc.2007.12.086

• VEGF
• albumin
• hypoxia
• proximal tubule
• HIF
• proteinuria

Reduction of vascular endothelial growth factor (VEGF) expression plays a crucial role in chronic kidney disease (CKD). In order to clarify a cause of VEGF suppression in CKD, we examined an interaction between proteinuria and VEGF. Rat proximal tubular cells were subjected to hypoxia with or without albumin to mimic proteinuric conditions, and VEGF expression was assessed by real-time quantitative PCR and enzyme-linked immunosorbent assays. Albumin significantly reduced VEGF expression under hypoxia. Luciferase activity controlled by hypoxia-responsive element (HRE) was suppressed by albumin, demonstrating suppression of the hypoxia-inducible factor (HIF)/HRE pathway. Studies utilizing a proteasome inhibitor and a prolyl hydroxylase inhibitor showed that mechanisms of HIF/HRE pathway suppression by albumin load did not involve degradation of HIT protein levels. Further, albumin did not change HIF mRNA levels. Our data, for the first time, suggest a clear 'link' between proteinuria and hypoxia, the two principal pathogenic factors for CKD progression.

• 出版日期2008-3-7
• 单位河北医科大学