Connective Tissue Growth Factor Promotes The Proliferation Of Myofibroblast Through ERK-1/2 Signaing Pathy

Objective:To investigate the effects and mechanism by which Connective tissue growth factor promotes the proliferation of myofibroblast activated by TGF-β1.Methods:Human embryonic lung fibroblast (HELF) cells were pretreated by TGF-β1 for 48hours so that the cells transform into myofibroblasts, and then the cells were divided into control group, CTGF treated group, and PD98059 intervene group. The protein level of a-SMA was determined by Western blot analysis. The method of MTT was adopted to detect the effect of myofibroblasts proliferation.Results:The protein expression level of a-smooth muscle actin of CTGF treated group is significantly higher than that of control group (P<0.01); the inhibitor of ERK-1/2 phosphorylation PD98059 significantly suppressed expression of a-SMA protein induced by CTGF (P<0.05); the myofibroblasts of CTGF treated group propagate significantly (P<0.01); the inhibitor of ERK-1/2 phosphorylation PD98059 significantly suppressed the proliferation induced by CTGF (P<0.05). Significant phosphorylation of ERK-1/2 was detected after incubation with CTGF for 15min in the cells pretreated by TGF-(31 (P<0.01), reach to the peak for 30min, decrease to basal level for 60 min.Conclusion:CTGF induced a proliferative response in TGF-β1 -initiated myofibroblasts, and this action is likely dependent on the activation of ERK-1/2 signaling pathway.