Effect Of MiRNA - 221 On Extracellular Matrix Of Airway Smooth Muscle Cells And Its Mechanism

ObjectiveTo investigate the expression of microRNA (miR) and extracellular matrix deposition in rat airway smooth muscle cells after stimulated by PDGF-BB and EGF.MethodStimulated the rat ASMCs by PDGF-BB and EGF. ASMCs will be divided into control group, PDGF-BB group and EGF group, then detect the expression of miR in ASMCs by quantitative RT-PCR technology. Western Blot was used to detect the expression level of type Ⅰ collagen and type Ⅲ collagen.ResultsStimulated the ASMCs by PDGF-BB, miR-221 expression increased.Stimulated by EGF in ASMCs, the level of miR-221 and miR-192 increased. PDGF-BB and EGF could induce the expression of type Ⅰ collagen and type Ⅲ collagen.ConclusionStimulated by PDGF-BB and EGF in ASMCs, the expression of microRNAs had different changes, and they could induce the desipotion of ECM.ObjectiveTo investigate the possible mechanisms of miRNA-221 on the extracellular matrix deposition of airway smooth muscle cellsMethodAirway smooth muscle cells were transfected with miR-221 mimics and the transfection efficiency of miR-221 was verified by RT-PCR. Western Blot was used to detect the expression level of type I collagen (COL1A2), type III collagen (COL3Al).Using gene chip technology to detect the changes of signaling pathway in extracellular matrix deposition of ASMCs stimulated by miRNA-221. Western Blot was used to detect the level of P-Akt and Akt. PI3K/AKT-inhibitor (LY294002) was used to observe the varieties of the level of COL1A2, COL3A1, P-Akt and Akt.ResultsAfter transfection with miR-221 mimics, the expression of miR-221 was significantly higher than that of the control group. Overexpression of miR-221, the levels of COL1A2, COL3A1 were increased.Bioinformatics analysis and Western Blot confirmed that PI3K-AKT pathway was involved in the extracellular matrix deposition of ASMCs. Stimulated by miRNA-221, PI3K/AKT pathway inhibitor LY294002 can reverse the overexpression of COL1A2, COL3A1 and P-Akt.ConclusionMiR-221 promoted the extracellular matrix deposition of airway smooth muscles by activating PI3K/AKT pathway.