Hydraulic pressure inducing renal tubular epithelial-myofibroblast transdifferentiation in vitro.
OBJECTIVE
The effects of hydraulic pressure on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) were investigated.


METHODS
We applied hydraulic pressure (50 cm H2O) to normal rat kidney tubular epithelial cells (NRK52E) for different durations. Furthermore, different pressure magnitudes were applied to cells. The morphology, cytoskeleton, and expression of myofibroblastic marker protein and transforming growth factor-beta1 (TGF-beta1) of NRK52E cells were examined.


RESULTS
Disorganized actin filaments and formation of curling clusters in actin were seen in the cytoplasm of pressurized cells. We verified that de novo expression of alpha-smooth muscle actin induced by pressure, which indicated TEMT, was dependent on both the magnitude and duration of pressure. TGF-beta1 expression was significantly upregulated under certain conditions, which implies that the induction of TEMT by hydraulic pressure is related with TGF-beta1.


CONCLUSIONS
We illustrate for the first time that hydraulic pressure can induce TEMT in a pressure magnitude- and duration-dependent manner, and that this TEMT is accompanied by TGF-beta1 secretion.
Li
Fei-yan
FY
Department of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, China.
Xie
Xi-sheng
XS
Fan
Jun-ming
JM
Li
Zi
Z
Wu
Jiang
J
Zheng
Rong
R
D000818:Animals; D002454:Cell Differentiation; D002460:Cell Line; D054338:Cell Transdifferentiation; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D007684:Kidney Tubules / Q000166:cytology* / Q000378:metabolism; D032446:Myoblasts / Q000166:cytology* / Q000378:metabolism; D011312:Pressure; D051381:Rats