Study on the role of allergic toxin C3a in epithelial mesenchymal transition of normal human bronchial epitahelium cells / 重庆医学

ABSTRACT

Objective To investigate the role of anaphylatoxin C3a on epithelial mesenchymal transition(MTT) in normal human bronchial epithelium cells and its molecular mechanism.Methods Normal human bronchial epithelium cells BEAS-2B were cultured,and divided into control group,rhC3a stimulation group,rhC3a+ C3a receptor(C3aRA)antagonist group,the morphological changes of cells were observed by microscope;cell proliferation was detected by MTT;the expression of TGF-β1 protein level in cell supernatant was evaluated by ELISA;the expression of C3aR mRNA and EMT related indicators mRNA changes were detected by RT-PCR;the expression of C3aR and Smad2/3,p38 MAPK pathway proteins were detected by Western blot.Results Cell morphology in 30,50 nmol/L rhC3a stimulation group was changed from normal cobblestone like to spindle shape,cell morphology in C3aRA antagonist group had no significant change when compared with the control group.The cell proliferation was reduced in 50 nmol/L rhC3a stimulation group(P=0.047);the levels of TGF-β1,p-Smad2/3,p-p38-MAPK protein were increased(P＜0.05),C3aR mRNA and protein levels were also significantly increased (P＜0.05) in 30 nmol/L rhC3a stimulation group when compared with control group,but the addition of 1 μmol/L C3aRA could reduce their expressions(P＜0.05).30 nmol/L rhC3a could induce the up regulation of α-SMA and N-cadherin mRNA,and decrease the expression of E-cadherin mRNA,adding 1 μmol/L C3aRA can antagonize this process (P＜0.05).Conclusion Anaphylatoxin C3a can induce EMT in normal human bronchial epithelium cells by combining C3aR,its mechanism may be involved in activating Smad2/3 and p38-MAPK pathway.