MicroRNA-93 Controls Perfusion Recovery Following Hind-Limb Ischemia by Modulating Expression of Multiple Genes in the Cell Cycle Pathway
Background—Micro-RNAs (miRs) are key regulators of gene expression in response to injury, but there is limited knowledge of their role in ischemia-induced angiogenesis, such as in peripheral arterial disease (PAD). Here, we used an unbiased strategy and took advantage of different phenotypic outcomes that follow surgically induced hind-limb ischemia (HLI) between inbred mouse strains to identify key micro-RNAs involved in perfusion recovery from HLI.
Methods and Results—From comparative micro-RNA profiling between inbred mouse strains which display profound differences in their extent of perfusion recovery following HLI, we found that the mouse strain with higher levels of miR-93 in hind-limb muscle before ischemia, and the greater ability to up-regulate miR-93 in response to ischemia had better perfusion recovery. In-vitro, over-expression of miR-93 attenuated hypoxia-induced apoptosis in both endothelial and skeletal muscle cells, and enhanced proliferation in both cell types. In addition, miR-93 over-expression enhanced endothelial cell tube formation. In-vivo, miR-93 over-expression enhanced capillary density and perfusion recovery from hind-limb ischemia, and antagomirs to miR-93 attenuated perfusion recovery. Both in-vitro and in-vivo modulation of miR-93 resulted in alterations in the expression of more than one cell cycle pathway gene in two different cell types.
Conclusions—Our data indicate that miR-93 enhances perfusion recovery from hind-limb ischemia by modulation of multiple genes that coordinate the functional pathways of cell proliferation and apoptosis. Thus, miR-93 is a strong potential target for pharmacological modulation to promote angiogenesis in ischemic tissue.
- Received December 26, 2012.
- Revision received March 5, 2013.
- Accepted March 25, 2013.