Emerging evidence supports the beneficial effect of
fibroblast growth factor-1 (
FGF1) on
heart diseases, but its application has been hindered by the short half-life and limited bioactivity of the free
protein. We designed an
injectable coacervate to facilitate robust
growth factor delivery, which would both protect and increase the bioactivity of
growth factors. In this study, a model for acute
myocardial infarction was established in mice, and the cardioprotective effect of the
FGF1 coacervate was investigated. Echocardiographic results showed that the
FGF1 coacervate inhibited ventricular dilation and preserved cardiac contractibility more than the free
FGF1 and the saline control within the 6-week duration of the experiments. Histological examination revealed that the
FGF1 coacervate reduced
inflammation and
fibrosis post-MI, significantly increased the proliferation of endothelial and mural cells, and resulted in stable arterioles and capillaries. Furthermore, the
FGF1 coacervate improved the proliferation of cardiac stem cells 6 weeks post-MI. However, free
FGF1, dosed identically, did not show significant difference from saline treatment. Thus, one injection of
FGF1 coacervate was sufficient to attenuate the injury caused by MI, and the results were significantly better than those obtained from an equal dose of free
FGF1.