Intervention Effects Of Bone Marrow-derived Mesenchymal Stem Cells Transplantation To The Bleomycin-induced Pulmonary Fibrosis Mice

Objective: Observed the intervention effects of bone marrow-derived mesen-chymal stem cells(BMSCs) transplantation to the bleomycin-induced pulmonaryfibrosis mice and to explore mechanisms.Methods: Bone marrow derived MSCs were harvested from male ICR mice invitro.150female ICR mice were randomly divided into3groups with50of eachgroup: negative control group (Group NC),positive control group (Group PC),mesenchymal stem cells transplanting group(group BMSCs).Group NC were givenwith50ul PBS by nasal instillation.Group PC and group BMSCs were made aspulmonary fibrosis models by nasal instillation of bleomycin(6ug/g,50ul).After24hours, the suspension of BMSCs were injected into mice via the tail vein of BMSCsintervention group with a concentration of1×107/ml,200ul.Five mice were weighedthe body weight and then sacrificed at days3,7,14,28after modeling in batch.Thenthe lung wet weight were weighed and lung tissues were restored to analyze thepathological changes such as HE staining,Masson staining,HYP content;The DNA oflung tissue was extracted for the detection sry gene;The RNA of lung tissue wasextracted for SP-C mRNA,AQP5mRNA.Results:1.Lung coefficient:at each time point, lung coefficient of group PC andgroup BMSCs were higher than group NC.But except3th, group BMSCs wereobviously lower than group PC.2.The pathological changes:compared with groupPC,after7th,the pulmonary inflammation of group BMSCs were decreasedobviously;after14th,the fibrosis extent of group BMSCs were decreased obviously.3.The content of HYP:At the3rdand7th,there is no significant differences of HYPcontent between three groups.At the14thand28th,group PC and group BMSCs`s thecontent of HYP were higher than group NC,but group BMSCs is lower than PC group.4.Sry gene detect:At each time point,we can detected the male mices`sry gene fromthe lung tissue of group BMSCs.5.The expression of SP-C mRNA:Expression ofSP-C mRNA of group PC and group BMSCs were higher than group NC.But except7th,group BMSCs were obviously higher than group PC.6.The expression of AQP5 mRNA:at each time point,the AQP5mRNA expression of group PC and groupBMSCs were lower than group NC; Compared with group PC,group BMSCs`sexpression of AQP5mRNA were obviously higher.Conclusion:1.The doner-derived injected via tail vein can arrive to the lungtissue of bleomycin-injuced pulmonary fibrosis mice and colonized there.Doner-derived BMSCs can decrease alveolitis and pulmonary fibrosis in mice withbleomycin-induced pulmonary fibrosis.2.The mechanism might be related to that thedoner-derived BMSCs may differentiate into the alveolar epithelial cells in the localand increase the expression of SP-C,AQP5in order to make recovery of lung stemcell bank and repair of lung injury.