Effect Of Matrine On Paraquat Induced Pulmonary Fibrosis In Mice And Its Mechanism

Objective: To investigate the effect of matrine on paraquat-induced pulmonary fibrosis in mice and its possible mechanism,and to provide a new theoretical basis for the clinical application of matrine in treating paraquatinduced pulmonary fibrosis.Methods: 24 SPF BALB/C mice were divided into the Control group,the Model group(PQ)and the Matrine group randomly,with 8 mice in each group.On the 1st day of the experiment,the PQ group and the Matrine group were given paraquat(18 mg/kg)single injection intraperitoneally,while the Control group were injected with the same amount of 0.9%Na Cl solution at the same time intraperitoneally.24 hours after modeling,the Matrine group were given matrine(100 mg/kg)every day,while the PQ group and Control group were given the same amount of 0.9 % Na Cl solution.HE staining and Masson staining were used to observe the pathological changes of lung tissues,and Ashcroft score was performed.The content of hydroxyproline(HYP)in lung tissue of mice in each group was detected by alkaline water method.The expression levels of collagen-I and collagen-III were detected by Western-blotting.The expression of epithelial-mesenchymal transition(EMT)related proteins were detected by immunofluorescence staining.The m RNA expression levels of Wnt/β-catenin signaling related proteins were detected by q PCR.Results: 1.General situation: the mice in the Control group were lively and active,sensitive to stimulation,without cyanosis around their mouths,eating and drinking normally,and gaining weight steadily;In PQ group,the mice were dispirited,breathless,weak,easily to catch,and weight loss.Compared with the PQ group,the symptoms of Matrine group mice were improved;2.Pathological changes of lung tissue: Pathological changes of lung tissue in PQ group mice were obvious,and obvious blue collagen fibers were deposited.Ashcroft score of pulmonary fibrosis was higher than that of the Control group(6.27±0.27 vs 0.34±0.09,P<0.001),while pathological changes of lung tissue of mice in the Matrine group were improved and Ashcroft score was lower than that of the PQ group(4.28±0.28 vs 6.01,P<0.001);3.Collagen deposition: Compared with the Control group,the contents of hydroxyproline,collagen I and collagen III in the PQ group were significantly higher(P<0.001),which were 1.836±0.121 vs 0.836±0.033,0.686±0.0121 vs 0.268±0.016 and0.455 0.016 respectively.The contents of hydroxyproline,collagen I and collagen III in Matrine group decreased(P<0.001),which were 1.227±0.055 vs1.836±0.121,0.463±0.014 vs 0.686±0.0121,0.286±0.018 vs 0.455±0.027respectively;4.Expression of EMT-related proteins: The expression of α-SMA and Vimentin in PQ group was higher than that in Control group(P<0.001),which were 5899.99±592.71 vs 1205.12±143.31,6141.37±478.63 vs995.60±175.74,respectively.The expression of E-cardherin protein was lower than that of the Control group(P<0.001),which was 628.46±58.13 vs3687.72±411.80,however,the expression of α-SMA and Vimentin protein in Matrine group was lower than that in PQ group(P<0.001).They were2226.9±300.88 vs 5899.99±592.71,2176.62±286.54 vs 6141.37±478.63,respectively.Compared with the PQ group,the expression of E-cardherin protein increased to 2201.71 168.09 vs 628.43(P<0.001);5.Expression of target genes related to Wnt/β-catenin signaling pathway: Compared with the Control group,the expression of β-catenin,MMP-2 and cyclin D1 in lung tissue of mice in PQ group increased(P<0.001).They were 3.277±0.270 vs0.843±0.178 、 3.377±0.240 vs 0.883±0.115 、 3.030±0.219 vs 0.893±0.110,respectively.Compared with the PQ group,the expression levels of β-catenin,MMP-2 and cyclin D1 in lung tissue of Matrine mice.They were 2.123±0.103 vs 3.277±0.270,2.447±0.190 vs 3.377±0.240,2.177±0.186 vs 3.030±0.219,respectively,and the differences of these indexes were statistically significant.Conclusion: 1.Matrine can improve paraquat-induced pulmonary fibrosis in mice,reduce collagen content in lung tissue and collagen fiber deposition;2.Paraquat-induced pulmonary fibrosis activated EMT process.After matrine intervention,the contents of α-SMA and Vimentin in alveolar epithelialmesenchymal cells decreased,while the contents of E-cadherin increased,suggesting that matrine can inhibit EMT process;3.Matrine can inhibit the expression levels of β-catenin,MMP-2 and cyclin D1 in lung tissue of mice with pulmonary fibrosis,which indicates that matrine may improve pulmonary fibrosis by regulating the expression of Wnt/β-catenin pathway in pulmonary fibrosis.