الملخص
Objective To investigate the effect and mechanism of human umbilical cord mesenchymal stem cell exosomes(Exo)on pulmonary inflammation in chronic obstructive pulmonary disease(COPD)rats.Methods A total of 18 male SD rats were randomly divided into the control group,the COPD group and the COPD + Exo group with 6 rats in each group.COPD rat model was estalished by giving cigarette smoke and lipopolysaccharide(LPS)inhalation in the COPD group and the COPD + Exo group.Rats in the COPD + Exo group were injected with 100 μL of human umbilical mesenchymal stem cell exosome diluent(containing 2×107 exosomes)via tail vein.The control group and the COPD group were given equal amounts of phosphate buffered solution.One week after intervention,rats were killed and the peripheral blood,alveolar lavage fluid(BALF)and lung tissue samples were collected.The histopathological changes in lung tissue of each group were observed using Hematoxylin and Eosin(HE)staining.The number of inflammatory cells in peripheral blood was counted by fully automated hematology analyzer.The serum levels of IL-1β,IL-6 and TNF-α were detected by enzyme-linked immunosorbent assay(ELISA).The expression levels of IL-1β,IL-6 and TNF-α mRNA in lung tissue were detected by qRT-PCR.Western blot assay was used to detect the protein expression levels of TLR4,p-NF-κB p65 and IκBα in lung tissue.Results In the control group,the structure of pulmonary alveolus was intact and regular,while in the COPD group,the structure of alveolus was disordered,some alveolus expanded irregularly,fused into bullae and even ruptured.The alveolar septa were widened and filled with a large number of inflammatory cells.Compared with the COPD group,the COPD+ Exo group had more intact alveolar structure and less infiltration of inflammatory cells in the alveolar septum.The inflammatory cells in peripheral blood decreased.The expression levels of IL-1β,IL-6 and TNF-α in serum and lung tissue were decreased(P<0.05).The expression of TLR4 and IκBα protein in lung tissue were increased,while the expression of p-NF-κb p65 protein decreased(P<0.05).Conclusion Human umbilical cord mesenchymal stem cell exosomes can alleviate pulmonary inflammation in COPD rats by modulating TLR4/NF-κB signaling pathway,thereby playing a lung-protective effect.
الملخص
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.
الملخص
Objective To explore PGD2 biological characteristics in L-929 mice lung fibroblasts cell by Laropiprant is a specific in-hibitor of PGD2 receptor regulation of TGF-β1/Smads signaling pathway .Provide further basis research to explore the molecular mechanisms of airway fibrosis .Methods The cells divided by Laropiprant concentration 0 .3 μmoL group ,1 .0 μmoL group ,3 .0μmoL group ,10 .0 μmoL group ,30 .0 μmoL and the control group .Each group were added TGF-β2 (2 .5 ng/mL) were cultured for 24 h after stimulation with the corresponding concentrations of Laropiprant 24 h ,TGF-β1 Smad3 and Smad4 expression were detected by PCR and WB ,respectively .A randomized approach ,using different concentrations of Laropiprant acts on cells at different times (12 ,24 ,48 ,72 h) by MTT assay for cell growth Laropiprant inhibition .Results TGF-β1 ,Smad3 and Smad4 mRNA expression de-creased with the addition of Laropiprant concentration increases ,there was significant difference compared with the control group with (P<0 .05) .TGF-β1 ,Smad3 and Smad4 protein expression decreased with the addition of Laropiprant concentration increases ,there was significant difference compared with the control group with (P< 0 .05) .Cell growth inhibition rate decreased with Laropiprant concentration increasing and cell culture time growth ,Laropiprant in concentration 1μml ,reaction time was 24 to 36 h ,the cell growth inhibition was significantly improved .Conclusion PGD2-DP1 expression in L-929 mouse lung fibroblasts cell may be associated with TGF-β1/Smads regulation .growth inhibition rate decreased with Laropiprant concentration increasing and cell culture time growth ,re-action time prolong ,the cell growth inhibition was significantly improved .