Lipopolysaccharide preconditioning improves therapeutic effect of MSC transplantation in a rat model of myocardial infarction

doi:10.3969/j.issn.1009-0126.2014.10.018

Abstract：Objective To study whether lipopolysaccharide (LPS ) preconditioning improves the therapeutic effect of MSC transplantation in a rat model of acute myocardial infarction (AMI) . Methods MSC were divided into control group 1 ,LPS preconditioning group ,and Toll-like recep-tor 4 (TLR4) blocking group .Expression of syndecan-4 mRNA and protein in MSC was detected by quantitative analysis .The MSC were then divided into control group 2 ,LPS preconditioning group 2 ,and TLR4 blocking group 2 .Overexpressed plasmids in MSC-transfected syndecan 4 served as an overexpression group and silence syndecan 4 in MSC served as a combination group . Proliferation of MSC was assayed by MTT .The MSC were implanted into AMI rats .Angiogene-sis density was detected .Results The expression level of syndecan 4 mRNA and protein in MSC was significantly higher in LPS preconditioning group than in control group 1 and TLR4 blocking group 1 (P=0 .000) .The cardiac function was significantly better in LPS preconditioning group than in control group 2 and TLR4 blocking group 2 (P<0 .01) .The proliferation rate of MSC and angiogenesis density were significantly higher in overexpression group than in control group 2 and TLR4 blocking group 2 (P=0 .009) .The proliferation rate of MSC was lower while the MI size was larger and the mortality was higher in combination group than in other groups (F=16 .739 , P=0 .013;20 .0% vs 13 .3% vs 20 .0% ,χ2 =13 .755 ,P=0 .000) .Conclusion LPS preconditioning up-regulates the syndecan 4 expression in MSC ,thus improving the therapeutic effect of MSC transplantation on AMI .