The Effects Of Lysophospholipids Acid In Endothelial Progenitor Cells Transplantation Of The Rat With ALI

AIMS:This study was to explore the effection of LPA that improvement of survival and migration activities in EPCs,in this study we pretreated endothelial progenitor cell by LPA,and then transplanted it to the pulmonary to treate the acute lung injury of rats induced by LPS. The results provided experimental evidences for treatment biology of ALI.METHODS:ALI model, EPCs were isolated from SD rat bone marrow by density gradient centrifugation.Isolated cells were seeded in DMEM-F12M medium (contain 20%fetal bovine serum); EPCs were separated、cultured and pretreated by LPA in vitro,and then tested the activity of EPCs.Further, EPCs treated with LPA overnight,LPS induced tail intravenous injection of EPCs,the LPS with labeled endothelial progenitor cells suspension were injected into the rat model of acute lung injury, observed of effection of EPCs transplantation on acute lung injury of rats. Rats were randomly divided into four groups:normal control group、the LPS controls group (LPS+PBS group)、 EPCs controls group (LPS+EPCs group) and the treatment group (LPS+EPCs+LPA group), the rat models of ALI were made through the rat caudal vein by LPS. LPS+EPCs group, infected with labeled endothelial progenitor cells suspension (EPCs2×1006/0.5ml).The treatment group (LPS+EPCs+LPA group), EPCs pretreated with LPA was injected into the rat caudal vein of ALI model.Both of them were evaluated by HE staining and measuring dry/ wetafter 1 and 7 days later. TLR4 mRNA and NF-KBmRNA expression levels were examined using RT-PCR. RESULTS:EPCs were successful isolated and cultured; LPA could improve the proliferation of EPCs. EPCs transplanted showed that the EPCs reduced pulmonary Inflammatory cells soak、cellular injury and dry/wet weight on rats of ALI; LPA pretreatment, the content of endothelial progenitor cells in the peripheral blood significantly improved; the expression of TLR4 mRNA and NF-KBmRNA was declined in the lung tissue. Compared with EPCs transplantation group, in pretreatment by LPA group significantly reduced inflammation cells pulmonary Inflammatory cells soak、cellular injury and dry/wet weight in acute lung injury rat; the expression of TLR4 mRNA and NF-KBmRNA in lung tissue were declined (p< 0.001).CONCLUSIONS:1. EPCs was successfully isolated from rat bone marrow by density gradient centrifugation method; 2. Intravenously administrated EPCs can successfully engraft to lung tissue of the ALI rats.3. There are significant improvements in the lung injury by transplanted EPCs. The beneficial effects of the EPC treatment is likely to come from restoring damaged endothelium,repairing the damage of blood vessels and reducing the inflammatory cell infiltrates and adhesion, reducing the inflammatory response,restoring the pro-inflammatory and anti-inflammatory balance by regulating the immune cells and lowering promote inflammation response.4. The experiment results show that LPA promotes EPCs proliferation and antiapoptosis and obviously cured injury organ of ALI in rats. These results provided new ideas for the therapy of ALI.