Long Non-coding RNA Growth Arrest Specific-5(GAS5):A Potential Biomarker For Early Diagnosis Of Severe Asthma

Object:To explore the possibility of GAS5 acting as a biomarker for early diagnosis of severe asthma.Methods:Peripheral blood was obtained from healthy volunteers,patients with steroid-sensitive asthma and severe asthma and peripheral blood mononuclear cell?PBMC?were separated.Western blotting was used to detect GR^Ser226 of three groups after dexamethasone treatment,and q PCR was used to detect GAS5 level of three groups before and after dexamethasone treatment in vitro.BALB/c mice?n=24,aged6 weeks?were randomly and averagely divided into 3 groups:control group,asthma group and dexamethasone group.The mice were sensitized and challenged with ovalbumin?OVA?and lipopolysaccharide?LPS?to produce a steroid-resistant murine model of asthma.q RT-PCR was used to detect the expression of GAS5 in lung tissue of mice.HBECs?Human bronchial epithelial cells?were cultured,transfected with mi R-9 mimics,JNK1 inhibitor and interfered with IL-2+IL-4 and dexamethasone.Western blotting was used to detect the expression of GR^Ser226 and q PCR was used to detect the level of GAS5 in HBECs.Results:The steroid-sensitive asthma group had an over 20 times higher GAS5 level in PBMC?P<0.001?,but severe asthma group was over 15 times lower?P<0.001?after dexamethasone treatment.The expression of GR^Ser226 of severe asthma group was significantly higher than that of control group and steroid-sensitive asthma?P<0.001?.In lung tissue of mice,the GAS5 level of dexamethasone group was lower than asthma group?P<0.001?and control group?P<0.05?.Interference with IL-2 and IL-4 or transfection of mi R-9 mimics could both evaluate the expression of GR^Ser226in HBECs?P<0.001?.The GAS5 level in HBECs after IL-2+IL-4+dexamethasone interference was lower than HBECs only treated with IL-2+IL-4?P<0.001?.HBECs transfected with mi R-9 mimics expressed a higher level of GAS5 than that after dexamethasone treatment?P<0.05?.However,transfecting with JNK1 inhibitor could reverse the expression of GAS5 in HBECs transfected with mi R-9 mimics and interfered with dexamethasone,making it much higher than that of HBECs only transfected with mi R-9 mimics and interfered with dexamethasone but similar with HBECs interfered with dexamethasone solely.But the level of GAS5 in HBECs interfered with IL-2+IL-4 and dexamethasone was not affected by JNK1 inhibitor.Conclusion:GAS5 has the possibility of acting as a biomarker for early diagnosis of severe asthma by comparing GAS5 level of PBMCs of patients with severe asthma before and after glucocorticoids treatment.And the expression difference of GAS5 is due to GR^Ser226 phosphorylation.