Effect Of Stem Cell Factor On Phenotypic Changes And TGF-? 1 Expression In Human Renal Tubular Epithelial Cells

Objective To investigate the effects of stem cell factor?SCF?on phenotypic change and the expression of TGF-?₁ and fibronectinin human renal tubular epithelial cells line?HK-2?in vitro,andtoclarifytheimpactof SCFon developmentand progressionofrenal fibrosis.Methods HK-2 cells cultured in vitro were divided into four groups by SCF concentrations: control,10 ng/mL,50 ng/mL,100 ng/mL.The HK-2 cells were divided into five groups according to the stimulation time of 50 ng/mL SCF: control,6 hours,12 hours,24 hours,48 hours.The morphology of HK-2 cells was detected by the inverted phase contrast microscope.The expression of ?-Smooth muscle actin??-SMA?,transforming growth factor beta 1?TGF-?₁?and fibronectin at both m RNA and protein levels was detected by Real-time PCR and Western blot,while the supernatant level of TGF-?₁ was measured by ELISA.Results?1?With the increase of the concentration and the extending of stimulation time of SCF,HK-2 cells were graduallystretched for spindle shape from roundor round-like shape.?2?Real-time PCR and Western blot showed that the expressions of ?-SMA,TGF-?₁ and fibronectin at both m RNA and protein levels were increased in HK-2 cells treated with SCF?10 ng/mL,50 ng/mL,100 ng/mL?compared with the control group.With the concentration of SCF increased,the expressions of ?-SMA,TGF-?₁ and fibronectin were gradually increased?P < 0.05?.And the expressions of ?-SMA,TGF-?₁ and fibronectin in HK-2 cells treated with SCF?the concentration was 50 ng/mL?for different stimulation time were gradually increased compared with controlgroup.Compared with the control group,the expressions of these factors were slightly up-regulated after 6 hours?all P > 0.05?,significantly up-regulated after 12 hours?all P < 0.05?,and reached peak after 24 hours?all P < 0.01?,no further increased after 48 hours.?3?ELISA revealed that the secretion of TGF-?₁ in supernatant was roughly synchronized with the expression of intracellular TGF-?₁in a concentration-and time-dependent manner?P < 0.05?.Conclusion SCF can promote the transdifferentiation of HK-2 cells into myofibroblasts and induce the expressions of TGF-?₁ and fibronectin in HK-2 cells in vitro.