Effects Of Mechanical Stretch On Airway Remodeling Associated Factors Expression And Signaling Pathway In Human Bronchial Epithelioid Cells

Objective To investigate the effects of mechanical stretch on transforming growth factor-?1(TGF – ?1),fibroblast growth factor-2(FGF – 2)expression and signaling pathway in human bronchial epithelioid(16HBE)cells.Methods Using Flexcell-4000 cell loading device with flexible substrate to stretch human airway epithelial cells,the stretching force is 15%,at frequency of 1 Hz,stretching for 0.5 h,1 h,1.5 h and 2 h.And choose the higher expression of TGF-?1,FGF-2 and Ca2+ group to carry out intervention experiments,cells were pretreated with canonical transient receptor potential 1(TRPC1)channel antagonist SKF96365,protein kinase C(PKC)inhibitor HA-100,and thereafter mechanical stretch was applied.Cells were divided into 4 groups: a control group(which is not going through the mechanical stretch),a mechanical stretching group,a mechanical stretching + SKF96365 group,a mechanical stretching + HA-100 group.Western Blot was performed to show the expression of TGF-?1,FGF-2 protein,the level of TGF-? 1 and FGF-2 mRNA expression was detected by Quantitative Real-time PCR,and the intracellular Ca2+ fluorescence intensity was measured by Flow Cytometry.Results 16 HBE cells in the 15% stretching force,compared with the blank control group,TGF-?1 and FGF-2' protein and mRNA,intracellular Ca2+ fluorescence intensity was significantly increased(p<0.05)at 4 time points.After 0.5 h,the increasing rate is the highest,after 1 h,it decreased,but 1.5 h later and 2 h later,the expression gradually increased again.TGF-?1 protein and mRNA,FGF-2 protein and mRNA,intracellular Ca2+ fluorescence intensity in 0.5 h stretch+SKF96365,0.5 h stretch+HA-100 group were significantly lower than those in stretch group(p<0.05).Conclusion Mechanical stretch may induce Ca2+ influx and up-regulate TGF-?1,FGF-2 expression in 16 HBE cells by activating PKC,and then TRPC1.