Co-treating Mesenchymal Stein Cells With IL-1β And TNF-α Increases VCAM-1Expression And Improves Post-ischemic Myocardial Function

Background Inflammatory mediators are released by the myocardium after myocardialischemia as a response to tissue injury, and contribute to the repair and adaptiveresponses. Treated mesenchymal stem cells (BMMSCs) with a variety of inflammatoryfactors could activate a series of biological processes include paracrine，thus enhancecell-mediated cardioprotection after myocardial infarction (MI).Aims This study was to investigate adhesion and migration ability of IL-1β and TNF-αpretreated BMMSCs, the effect of IL-1β and TNF-α treatment on BMMSCs,expression of vascular cell adhesion molecule-1(VCAM-1), and the cardiac functionof ischemia rats, and to explore whether the combination of two inflammatorycytokines could enlarge the effect.Methods In migration assay, control and treated cells were seeded on the upper of thetranswell chamber, cytokine was added in the medium separately, after12h culture,cells migrated to the lower of the chamber were counted. Then cells were stimulatedwith IL-1β (10ng/ml,20mg/ml), TNF-α (10ng/ml,20mg/ml), IL-1β (10ng/ml)+TNF-α (10ng/ml) for24h, control group without treated. Control and treated cellswere used in the subsequent expriments. In adhesion assay, cells were digested,adjusted to1×105，seeded in the plates,20minutes later, cells adhesion to the platewere counted. After stained with PE-VCAM-1, expression of VCAM-1was assessedwith FCM, mRNA expression of BMMSCsVCAM-1was detected by RT-PCR. Proteins were denatured and then expression of the adhesion molecule was detected byWestern Blot. BMMSCs in control and treated groups were injected into the free wallof left ventricle, cardiac function was measured by two-dimensional echocardiography,and collagen expression in myocardium examined by Masson staining.Results We found that IL-1β and TNF-α pretreated significantly up-regulated adhesionand migration abilities of BMMSCs when compared with the control group, and thecytokine pretreatment significantly increased VCAM-1expression of BMMSCs ingene and protein levels. Thus greatly improved cardiac function compared with controlgroup (P<0.01). Furthermore, the combination group benefited the most. However,there was no significant difference between the10ng/ml group and20ng/ml groupwhich stimulated with single cytokine (P>0.05).Conclusion Stimulating BMMSCs with IL-1β and TNF-α can elevate the productionof VCAM-1and improve post-ischemic myocardial functional recovery after ischemia.Treating BMMSCs with two cytokines may be useful to fully realize the potential ofcell-based therapies for ischemic tissues.