Glucagon-Like Peptide-1 (Glp-1) Improved Diabetic Lung Fibrosis Via Ampk And Microrna-27a (Mir-27a)

Background: Extracellular matrix proliferation is an issue which leads to lung tissue damage in diabetes mellitus. Glucagon-like peptide-1 (GLP-1) analogues can improve the proliferation of extracellular matrix in diabetic pulmonary disease. In this study, we investigated the effect of GLP-1 on pulmonary fibrosis through the AMPK/microRNA-27a (miR-27a) pathway. Methods: Human embryonic lung fibroblast (MRC-5) cells were cultured with a high-glucose medium, and were treated with miR-27a inhibitor, GLP-1 analogues, and AMPK inhibitor. Cell Counting Kit-8 (CCK8) detected the proliferation of MRC-5 cells. The fibrosis-related genes were analyzed, including Col-IV, fibronectin, NF-KB p65, ?-SMA, and TGF-131. Bioinformatics and dual-luciferase reporter assays were used to identify the targets for miR-27a. Results: Compared with the control group, the expression of miR-27a in the hyperglycemic group was significantly up-regulated (P<0.01) and the expression of peroxisome proliferator-activated receptor ? (PPAR?) significantly down-regulated (P<0.01). The expression of Col-IV, fibronectin, NF-KB p65, ?-SMA and TGF-131 increased significantly (P<0.01). The expression level of apoptosis factor caspase-3 decreased significantly (P<0.01). MiR-27a inhibitor could reverse the expression of these proteins. The effect of GLP1 on miR-27a was time- and concentration-dependent. After pretreating MRC-5 cells via GLP-1, with or without compound C (AMPK inhibitor), the expression of miR-27a in the GLP-1 treated group was significantly lower than that in Vehicle group. The expression of miR-27a was increased after inhibition of the AMPK pathway. A predictive TargetScan algorithm showed that the PPAR? gene was a potential target of miR-27a. MiR-27a was also shown to target 3'-UTR of PPAR?.Background: Extracellular matrix proliferation is an issue which leads to lung tissue damage in diabetes mellitus. Glucagon-like peptide-1 (GLP-1) analogues can improve the proliferation of extracellular matrix in diabetic pulmonary disease. In this study, we investigated the effect of GLP-1 on pulmonary fibrosis through the AMPK/microRNA-27a (miR-27a) pathway. Methods: Human embryonic lung fibroblast (MRC-5) cells were cultured with a high-glucose medium, and were treated with miR-27a inhibitor, GLP-1 analogues, and AMPK inhibitor. Cell Counting Kit-8 (CCK8) detected the proliferation of MRC-5 cells. The fibrosis-related genes were analyzed, including Col-IV, fibronectin, NF-KB p65, alpha-SMA, and TGF-131. Bioinformatics and dual-luciferase reporter assays were used to identify the targets for miR-27a.Results: Compared with the control group, the expression of miR-27a in the hyperglycemic group was significantly up-regulated (P<0.01) and the expression of peroxisome proliferator-activated receptor gamma (PPAR gamma) significantly down-regulated (P<0.01). The expression of Col-IV, fibronectin, NF-KB p65, alpha-SMA and TGF-131 increased significantly (P<0.01). The expression level of apoptosis factor caspase-3 decreased significantly (P<0.01). MiR-27a inhibitor could reverse the expression of these proteins. The effect of GLP1 on miR-27a was time-and concentration-dependent. After pretreating MRC-5 cells via GLP-1, with or without compound C (AMPK inhibitor), the expression of miR-27a in the GLP-1 treated group was significantly lower than that in Vehicle group. The expression of miR-27a was increased after inhibition of the AMPK pathway. A predictive TargetScan algorithm showed that the PPAR gamma gene was a potential target of miR-27a. MiR-27a was also shown to target 3'-UTR of PPAR gamma.Conclusions: MiR-27a plays an important regulatory role in diabetic pulmonary fibrosis. GLP-1 could down-regulate the expression level of miR-27a by activating AMPK. Furthermore, the target gene PPAR gamma was up-regulated, consequently improving extracellular matrix proliferation in MRC-5 cells.