Acta Academiae Medicinae Sinica

Acta Academiae Medicinae Sinica

Acta Academiae Medicinae Sinica ›› 2008, Vol. 30 ›› Issue (6): 703-710.doi: 10.3881/j.issn.1000-503X.2008.06.016

• Original Articles • Previous Articles     Next Articles

Relationship between the Effect of Vascular Endothelial Growth Factor on Epithelial-mesenchymal Transition of HK-2 Cells and the Expressions of Bone Morphogenetic Protein-7 and Inhibitor of DNA Binding/Differentiation

HE Chun-mei;ZHENG Fa-lei;LIAN Yao-guo;LIU Yan-ping   

  1. Department of Nephrology,PUMC Hospital,CAMS and PUMC,Beijing 100730,China
  • Received:2007-11-13 Revised:1900-01-01 Online:2008-12-30 Published:2008-12-30
  • Contact: ZHENG Fa-lei

Abstract: ABSTRACT:Objective To examine the relationship between effect of vascular endothelial growth factor (VEGF) on epithelial-myofibroblast transition(EMT)of HK-2 cells and changes in expressions of bone morphogenetic protein-7 (BMP-7) and inhibitor of DNA binding/differentiation (Id)2, Id3. Methods The cultured HK-2 cells were co-treated with transforming growth factor-β1 (TGF-β1) (5 ng/ml) and VEGF165 (0.1, 1, 10, 100 ng/ml), or with TGF-β1 (5 ng/ml) and VEGF receptor-1 neutralized antibody (10 μg/ml), and were also co-treated with TGF-β1 (5 ng/ml) and VEGF165 (100 ng/ml) with or without activin receptor-like kinase 6 (Alk6)/Fc Chimera(2 μg/ml, to neutralize endogenous BMP-7)for 48 hours. mRNA and protein expressions of α-smooth muscle actin (α-SMA), E-cadherin, BMP-7, Id2 and Id3 of HK-2 cells were assessed with double-stain immunocytochemistry, real-time PCR and Western blot respectively. Results Compared with normal controls, α-SMA expression significantly increased, while E-cadherin, BMP-7, Id2, and Id3 mRNA and protein expressions markedly decreased in HK-2 cells treated with TGF-β1 (5 ng/ml) (P<0.05). VEGF165 interrupted TGF-β1 induced α-SMA expression in a dose-dependent manner and upregulated BMP-7, Id2 mRNA and protein expressions of the cells(P<0.05). α-SMA expression increased, while E-cadherin, BMP-7, and Id2 expressions decreased further in HK-2 cells co-treated with TGF-β1 and VEGFR1 antibody compared with normal controls (P<0.05). When endogenous BMP-7 was neutralized with Alk6/Fc Chimera in the cells co-treated with TGF-β1 and VEGF165, α-SMA expression upregulated (P<0.05), while Id2 was not changed. Conclusions VEGF165 may partially inhibit TGF-β1-induced EMT of HK-2 cells in vitro. This effect is related to the upregulated expressions of BMP-7 and Id2. Id2 may be upregulated directly by VEGF165, but not related to BMP-7.

Key words: vascular endotdelial crowtd factor, epitdelial-mesencdymal transition, bone morpdocenetic protein-7, indibitor of dna bindinc/differentiation