Inhibitory effect of vascular endothelial growth factor on transforming growth factor β1-induced epithelial-mesenchymal transition of HK2 cells and its relationship with connective tissue growth factor and PI3K-Akt pathway
10.3760/cma.j.issn.1001-7097.2009.06.012
- VernacularTitle:血管内皮生长因子抑制肾小管上皮间充质转化及其与结缔组织生长因子和PI3K-Akt信号通路的关系
- Author:
Yaoguo LIAN
;
Chunmei HE
;
Falei ZHENG
- Publication Type:Journal Article
- Keywords:
Vascular endothelial growth factors;
Transforming growth factor beta 1;
Epithelial cells;
Connective tissue growth factor;
Epithelial-mesenchymal transition
- From:
Chinese Journal of Nephrology
2009;25(6):445-451
- CountryChina
- Language:Chinese
-
Abstract:
Objective To examine the relationship of the inhibitory effect of vascular endothelial growth factor(VEGF) on epithelial-mesenchymal transition (EMT) induced by TGF-β1 in HK2 cells with the expression of connective tissue growth factor (CTGF) and PI3K-Akt pathway. Methods The cultured HK2 cells were divided into the following groups: normal control group, TGF-β1 (5 μg/L) group, VEGF (100 μg/L) group, TGF-β1 plus VEGF group. LY294002 (25 μmol/L), the blocker of PI3K-Akt pathway, was added to each of above-mentioned groups for the second part of the study, α-smooth muscle actin (α-SMA) and E-cadherin expressions of HK2 cells were assessed with double-stain immunocytochemistry method. The mRNA and protein expressions of α-SMA and CTGF of cells were assessed with RT-PCR and Western blot. The expressions of fibronectin (FN) and collagen Ⅰ (Col Ⅰ) in medium were assessed with ELISA. Results The expressions of α-SMA and CTGF significantly increased in HK2 cells treated with TGF-β1 compared with those in normal control (P<0.05), while significantly decreased in cells co-treated with TGF-β1 and VEGF compared with those treated with TGF-β1 alone (P<0.05, respectively). The expression of E-cadherin was exactly opposite to that of α-SMA. When LY294002 was added to TGF-β1 and VEGF co-treated cells, the expressions of α-SMA, CTGF, FN and Col Ⅰ were markedly up-regulated, when compared with those without LY294002 treatment (P<0.05). Conclusion Inhibitory effect of VEGF on TGF-β1-induced EMT of HK2 ceils in vitro may be related to down-regulation of CTGF expression and reduction of FN and Col Ⅰ, which may be partly dependent on PI3K-Akt pathway.
