Expression data from Human Microvascular Endothelial Cells exposed or not to low-dose ionizing radiation

We have previously shown that low doses of ionizing radiation (LDIR) induce angiogenesis. In the present study we investigated their action in experimentally induced hindlimb ischemia. We demonstrated that 0.3 Gy, administered for four consecutive days, significantly improves blood perfusion in the murine ischemic limb by stimulating angiogenesis and arteriogenesis. This is achieved through durable and simultaneous up-regulation of a repertoire of pro-angiogenic factors and their receptors in endothelial cells, as evident in cells isolated from the irradiated gastrocnemius muscles. Moreover, we demonstrated that this mechanism is mediated via VEGFR signaling, since VEGFR inhibition abrogated the LDIR-mediated gene up-regulation and impeded the increase in vessel density. Importantly, the vasculature in an irradiated non-ischemic bed is not affected and no adverse effects associated to the use of LDIR were seen. These findings disclose an innovative, non-invasive strategy to induce therapeutic angiogenesis in a murine model of severe hindlimb ischemia, emerging as a novel approach in the treatment of Critical Limb Ischemia patients.

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