Knockdown of endogenous miR-377 enhances MSC-mediated myocardial angiogenesis in vivo.

<p>(<b>A</b>): Slice sections of heart samples, collected from MI rats 4 weeks after the injection of miR-engineered MSCs, were triple-stained with troponin I (cTnT) antibody (Ab) (for cardiomyocytes, red), α-smooth muscle actin (SMA) Ab (for vascular cells, green; white arrows) and DAPI (for nuclei, blue). Vascular density was measured in (A) MSC^Null group, (<b>B</b>) MSC^miR-377 group, and (<b>C</b>) MSC^Anti-377group. Capillary density was identified by Von Willebrand (vWF) staining (green; white arrows) in (<b>D</b>) MSC^Null group, (<b>E</b>) MSC^miR-377 group and (<b>F</b>) MSC^Anti-377 group. IPP software was used to quantitatively analyze (<b>G</b>) vascular density, and capillary density in different treatment groups. All values were expressed as means ± SE; n = 6 for each group. ^*<i>P</i><0.05 <i>vs.</i> MI;^#<i>P</i><0.05 <i>vs.</i> MI+MSC^Null.