LAUSR

BACKGROUND The development of heart failure after acute myocardial infarction (MI) was related to left ventricular (LV) pathological remodeling and dysfunction. Cardiac stem cells (CSCs) provided a new option to treat acute MI. This study was to investigate the effects of CSCs on structural and functional alteration in acute MI. METHODS Acute MI was induced in 20 Sprague-Dawley rats by ligation of the left anterior descending coronary artery. Two weeks after MI, animals were randomized into CSCs or control group. LV geometry and function were echocardiographically measured at baseline, 2, 4, and 6 weeks after MI. After measuring hemodynamics at 6 weeks after MI, hearts were harvested for tracing CSCs stained by PKH26 and testing expression of VEGF-α/TGF-β1 by RT-PCR and ELISA. RESULTS Two weeks after MI, there were significant decreases in interventricular septal systolic and diastolic thickness (IVSTs/d), while increases in LV systolic and diastolic dimension (LVDs/d). Consequently, this contributed to decreases in ejection fraction (EF) and fractional shorting (FS). With the treatment of CSCs for 4 weeks, significant better ejection fraction (EF) and fractional shorting (FS) were achieved in CSCs group accompanied by the reduction in LV systole and diastole dimension (LVDs/d). Besides, a significant improvement in the maximal rate of LV pressure development and decline (peak +dP/dt and -dP/dt, respectively) was observed. Moreover, significantly higher VEGF-α was expressed in CSCs group rather than TGF-β1. CONCLUSION CSCs significantly prevented structural and functional deterioration after MI with increasing expression of VEGF-α.