The Effect Of Mesenchymal Stem Cells And Stem Sell Factors On Peritoneal Dialysis-associated Peritoneal Fibrosis

Objective: The purpose of this study was to investigate the effect of mesenchymal stem cells on peritoneal fibrosis in peritoneal dialysis rats and the effect of mesenchymal stem cell supernatant(stem cell factor)on high glucose-induced human peritoneal mesothelial cell fibrosisMethods: Animal experiment: A total of 24 male Sprague-Dawley rats weighing200g-250 g were randomly assigned to four groups: Normal control group,Peritoneal fibrosis group,stem therapy group 1 and stem therapy group 2.Each group has 6rats.Normal control group: Rats received intraperitoneal(i.p.)injections of the of saline(100 ml/kg)every other day.In addition to the normal control group,all rats received i.p.injections of same volume of Lactate-G4.25% dialysate every other day and six of them used as peritoneal fibrosis group.Rats in stem cell therapy group 1received i.p.injections of 1ml human umbilical cord mesenchymal stem cells(HUC-MSCSs)(2*106)in the 7th and 14 th day of the injections of dialysate.Rats in Stem cell therapy group 2 received i.p.injections of 1ml HUC-MSCSs(2*106)in the14 th and 21 th day of the injections of dialysate.The peritoneal dialysis solution was taken after 28 days for peritoneal balance test,and the peritoneal tissue was removed for HE staining,Masson trichrome staining and immunohistochemical staining to observe the degree of peritoneal fibrosis and the expressions of EMT-related protein E-cadherin and Vimentin.Cell experiment:Normal control group: Human peritoneal mesothelial cells were cultured for 48 hours in RPMI 1640 medium with 10%heat-inactivated fetal calf serum and 100 U/ml penicillin/streptomycin.Fibrosis group:Human peritoneal mesothelial cells were cultured for 48 hours in the medium contain2.5% glucose to induce fibrosis.In the treatment group,human peritoneal mesothelial cells were cultured in high glucose medium for 24 hours,and then cultured in 5 ml of medium containing 50%,20%,10% and 5% umbilical cord mesenchymal stem cell supernatant for 24 hours.The changes of E-cadherin and Vimentin in peritoneal cells were observed by western-blot and the concentrations of TGF-β,TNF-α,MDA and SOD in the cell culture supernatant were detected by ELISA.Results:(1)Animal experiment: After peritoneal dialysis for 28 days,compared with the saline control group,the peritoneum in the model group was significantly thicker and the inflammatory cells infiltrated obviously.At the same time,the amount of peritoneal ultrafiltration decreased,significantly increased,decreased peritoneal function.E-cadherin expression decreased while Vimentin expression increased.On the contrary,compared with the model group,the peritoneum of treatment group 1and 2 was obviously thinned and the infiltration of inflammatory cells was alleviated.At the same time,the peritoneal ultrafiltration volume was significantly increased,the glucose transport volume was obviously decreased,and the peritoneal function was improved.E-cadherin expression increased while Vimentin expression decreased.The improvement of treatment group 1 was better than that of treatment group 2.(2)Cell experiment: Compared with the normal control group,the cells showed obvious fibrosis after adding high glucose medium for 48 h,the expression of Vimentin was obviously increased,while the expression of E-cadherin was inhibited.Meanwhile,the cell culture medium The MDA content increased while the SOD content decreased.The treatment group compared with the model group showed a significant reduction in Vimentin expression,while E-cadherin expression increased,while the cell culture medium MDA content decreased and SOD increased.At the same time with the treatment group,the increase of MSCs supernatant(stem cell factor)increased the therapeutic effect of improved stem cell factor.Conclusion: Mesenchymal stem cells can significantly improve peritoneal dialysis-related peritoneal fibrosis,reverse peritoneal EMT,improve peritoneal transport,and have better early application.Stem cells can significantly improve high glucose-induced human peritoneal mesothelial cell fibrosis and reverse EMT significantly reduced oxidative stress-induced inflammatory response.In a concentration-dependent manner.