Over-expression of HO-1 on mesenchymal stem cells promotes angiogenesis and improves myocardial function in infarcted myocardium

Abstract. heme oxygenase-1 (ho-1) is a stress-inducible enzyme with diverse cytoprotective effects,and reported to have an important role in angiogenesis recently. here we investigated whether ho-1 transduced by mesenchymal stem cells (mscs) can induce angiogenic effects in infarcted myocardium. ho-1 was transfected into cultured mscs using an adenoviral vector. 1 × 10 6 ad-ho-1-transfected mscs (ho-1-mscs) or ad-null-transfected mscs (null-mscs) or pbs was respectively injected into rat hearts intramyocardially at 1 h post-myocardial infarction. the results showed that ho-1-mscs were able to induce stable expression of ho-1 in vitro and in vivo. the capillary density and expression of angiogenic growth factors,vegf and fgf2 were significantly enhanced in ho-1-mscs-treated hearts compared with null-mscs-treated and pbs-treated hearts. however,the angiogenic effects of ho-1 were abolished by treating the animals with ho inhibitor,zinc protoporphyrin. the myocardial apoptosis was marked reduced with significantly reduced fibrotic area in ho-1-mscs-treated hearts; furthermore,the cardiac function and remodeling were also significantly improved in ho-1-mscs-treated hearts. our current findings support the premise that ho-1 transduced by mscs can induce angiogenic effects and improve heart function after acute myocardial infarction. © 2010 zeng et al; licensee biomed central ltd.