Effects Of Hepatocyte Growth Factor Genetically Modified Mesenchymal Stem Cells Conditioned Medium On Acute Lung Injury In Rats

Aims To explore the effects of hepatocyte growth factor genetically modified mesenchymal stem cells conditioned medium and mesenchymal stem cells conditioned medium on LPS induced acute lung injury in rats.Methods One hundred and seventeen sprague-dawley rats were randomized into the following three groups(n=39): HGF-MSC-CM group(H group)? MSC-CM group(M group)and LPS group.The rats were inhalated with LPS at a dose of 5 mg/kg to create a rat model of acute lung injury.Eight hours after LPS inhalation,HGF-MSC-CM 0.3 ml or MSC-CM 0.3 ml was respectively injected into the rats in group H or group M through tail vein.Same volume of DMEM was injected into LPS group as control.The rats experiment specimens were harvested at the first day,third day and seventh day after LPS inhalation.There were thirteen rats at each time point.Five rats were used to detect the content of Evans blue;the remaining eight rats were used to detect the changes of lung histopathology,lung injury scores,lung W/D,lung MPO activity,the concentration of serum inflammatory cytokines,and the expressions of PCNA and p-c-met.Lung tissues were collected and blood was taken for subsequent analysis.The pathological changes of lung tissue were observed by HE staining.The serum levels of TNF-?,IL-6 and IL-10 were determined by ELISA.The expression of PCNA was determined by immunohistochemistry.The expression of p-c-met was detected by western blot.Results Inflammatory cell infiltration,flaky bleeding,pulmonary edema,alveolar septal fracture and alveolar collapse were shown in LPS group.A small amount of inflammatory exudates were shown in M group.There were no obvious inflammatory exudates in H group and pulmonary structure integrity was maintained.Compared with LPS group,the lung injury scores were decreased in group M and group H on the first day and third day(p<0.05).On the seventh day,the lung injury scores were deceased in group H compared with group LPS(p<0.05).Lung injury scores were lower in group H than those in group M on the third day and seventh day(p <0.05).The W/D and MPO activities in group M and group H were significantly decreased than those in group LPS at three time points(p<0.05).The W/D and MPO activities were deceased in group H as compared with group M at three time points(p<0.05).Serum TNF-? levels in group H and M were decreased as compared with group LPS at three time points(p<0.05).The serum levels of TNF-? were decreased in group H than those in group M on the first day and third day(p<0.05).The serum levels of IL-6 in group M and group H were lower than those in group LPS and the serum levels of IL-6 were lower in group H than those in group M on the first day and third day(p<0.05).On the first day,the concentrations of IL-10 in group H were higher as compared with group M and group LPS(p <0.05).On the third day,the concentrations of IL-10 were higher in group M and group H as compared with group LPS and the concentrations of IL-10 were higher in group H as compared with group M(p <0.05).On the seventh day,the concentrations of IL-10 in group H were higher than those in group LPS and group M(p <0.05).On the first day,the leakage of Evans blue was decreased in group H as compared with group LPS and group M(p <0.05).The leakage of Evans blue in group M and group H was lower than that in group LPS on day 3 and the leakage of Evans blue was decreased in group H as compared with group M on day3(p <0.05).The leakage of Evans blue in group H was lower than that in group LPS on day 7(p <0.05).Compared with group LPS,the expression of PCNA was increased in group M and group H and the expression of PCNA was higher in group H than that in group M at three time points(p <0.05).On the seventh day,the expression of p-c-met was increased in group H and group M as compared with group LPS and the expression of p-c-met in group H was higher than that in group M(p <0.05).Conclusions The rat model of acute lung injury was successfully created.HGF-MSC-CM and MSC-CM played a potential therapeutic role in the protection against acute lung injury induced by LPS.The protective effects were enhanced by HGF-MSC-CM.