Host: The Japan Radiation Research Society, Chairman of the 52nd Annual Meeting, Toshiteru Okubo (Radiation Effects Research Foundation)
There is a concern that radiation induces vascular diseases as side effects after radiotherapies. Although radiation-induced atherosclerosis is one of such diseases, the mechanism remains controversial. Atherosclerosis is a multifactorial disease, and apoptosis in vascular smooth muscle cells is one of possible factors. Development of atherosclerosis is mediated by oxidative stresses and oxidized low-density lipoproteins, which can be apoptosis inducers. However, induction or development of atherosclerosis has not been investigated from the viewpoint of radiation-induced apoptosis in vascular smooth muscle cells. Here, using mouse aortic vascular smooth muscle cells, radiation-induced apoptosis in the cells was evaluated under the presence of mediators related to atherosclerosis. Radiation induced apoptosis of vascular smooth muscle cells very slightly. Although H2O2 had no effects on radiation-induced apoptosis, oxidized low-density lipoproteins had synergistic effects on the apoptosis. Mechanisms in radiation-induced apoptosis influenced by oxidized low-density lipoproteins will be discussed with the results of effects of kinase inhibitors on the apoptosis.
