The Mechanism Of Irisin Inhibits House Dust Mite-induced Inflammation And Apoptosis Of Airway Epithelial Cells

Objective:Irisin is a novel identified muscle factor that can induce the transformation of white adipose tissue into brown adipose tissue in the human body.It has been reported that irisin play an anti-inflammatory,anti-apoptosis and anti-oxidative stress role in a variety of chronic inflammatory diseases.This study will take the airway epithelial cells stimulated by house dust mite(HDM)as object to research the effect and the relate mechanisms of irisin on airway inflammation and apoptosis of asthma,which is helpful to provide new target and idea to the prophylaxis and treatment of asthma.Methods:1.The human bronchial epithelial cell(16HBE)were cultured with in RPMI 1640 culture medium with 10% of fetal bovine serum.After cells reached 85% confluence,the medium was replaced with serum-free culture medium for 12 h.Then the 16 HBE cells were treated with various concentrations of HDM(0、400、800、1200U/ml)for 24 h.2.Experiments were divided into four groups,blank control group,HDM400U/ml group,HDM800U/ml group,HDM1200U/ml group.Reactive Oxygen Species Assay Kit was used to detected the intracellular ROS generation.And qPCR was used to measure the interleukin(IL)-6,tumor necrosis factor-alpha(TNF-α)mRNA expression of the HDM-induced 16 HBE cell.3.The cells were pre-treated with or without irisin for 2h before exposure to various concentration of HDM for 24 h.Then Reactive Oxygen Species Assay Kit was used to detected the intracellular ROS generation.The IL-6,TNF-α mRNA expression of 16 HBE cell were measured by qPCR.Meanwhile,the phosphorylated and total P65 NF-κB and JNK proteins were detected by western blot.The pro-apoptosis protein cleaved-caspase3、BAX and the anti-apoptosis protein were also detected by western blot.Results:1.The quantitative assay showed that intracellular ROS in different concentrations of HDM stimulus group were obviously higher than NC group(P<0.05).And RT-PCR analysis showed a higher expression level of pro-inflammatory cytokine TNF-α and IL-6 mRNA in different concentrations of HDM than in NC group(P<0.05).2.Compared with the HDM group,Irisin significantly decreased the level of intracellular ROS of the 16 HBE cells(P<0.05).The released of the pro-inflammatory cytokine TNF-α and IL-6 mRNA was also decreased in irisin treated 16 HBE cells(P<0.05).And compared with control group,BCL-XL anti-apoptosis protein level was decreased and BAX and c-caspase3 pro-apoptosis protein levels were increased in HDM group(P<0.05),irisin intervention significantly increased the level of BCL-XL and decreased the levels of BAX and c-caspase3(P<0.05).Compared the control group,phosphorylated P65 NF-κB and JNK protein levels were significantly increased after HDM stimulated(P<0.05),and irisin intervention decreased the protein levels of phosphorylated P65 NF-κB and JNK(P<0.05).Conclusion:1.Irisin inhibited HDM-induced inflammation of human airway epithelial cells by reducing oxidative stress and inhibiting activation of NF-κB and JNK MAPK signaling pathways.2.Irisin inhibited HDM-induced apoptosis of human airway epithelial cells by increasing the anti-apoptosis protein level of BCL-XL and decreasing pro-apoptosis protein levels of BAX and cleaved-caspase3.