[The phenotypic transformation of renal tubular epithelial cells affected by pathological stimuli].
OBJECTIVE
To investigate the effects of low bovine serum, high glucose and high albumin on the phenotypic transformation of cultured renal tubular epithelial cells to mesenchymal cells.


METHODS
The human kidney proximal tubular cells were cultured for 7 days in the presence of low bovine serum (0.2 mol.L-1), high glucose (4.5 g.L-1) and high albumin (15 g.L-1), and morphological changes were assessed by electronic microscopy, immunohistochemistry stain and Western blot to show the phenotypic changes, including the expressions of cytokeratin, vimentin, collagen I and III, alpha-SMA, and TGF beta 1. The expression of collagen I mRNA was assessed by in situ hybridization.


RESULTS
Renal tubular epithelial cells cultured in low bovine serum, high glucose and high albumin, showed obvious morphologic changes, including elongated shape, reducing of microvillus and mitochondria, increasing of rough endoplasmic reticulum, and the appearance of actin microfilaments. Immunohistochemistry stain and Western blot showed the low expression of cytokeratin and high expression of vimentin, collagen types I and III, alpha-SMA, and TGF beta 1. The increasing expression of collagen I mRNA was assessed by in situ hybridization.


CONCLUSIONS
Lower bovine serum, high glucose and high albumin can induce the expression of TGF beta, and lead to the phenotypic transformation of tubular epithelial cells to mesenchymal cells.
Li
Ling
L
Department of Pathology, Peking University School of Basic Medical Sciences, Beijing 100083, China.
Zou
Wanzhong
W
Zhang
Bo
B
Wang
Shenglan
S
Guo
Hua
H
D002478:Cells, Cultured; D024042:Collagen Type I / Q000235:genetics; D004847:Epithelial Cells / Q000473:pathology*; D005355:Fibrosis; D006801:Humans; D007150:Immunohistochemistry; D007684:Kidney Tubules / Q000473:pathology*; D010641:Phenotype; D012333:RNA, Messenger / Q000032:analysis; D016212:Transforming Growth Factor beta / Q000235:genetics; D053773:Transforming Growth Factor beta1
D024042:Collagen Type I; D012333:RNA, Messenger; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1