Abstract
We previously showed that lifespan of human premature-aging syndrome model mouse (klotho) was prolonged by consecutively for the low dose-rate (0.63 mGy/h) gamma ray irradiation. We also found that antioxidant activities in various tissues of the mouse were enhanced by the irradiation, and maintained the level of calcium in the blood. Some researchers reported that the effects of lifespan prolongation were due to improve antioxidant functions or asthenia of insulin resistance. In addition, the role of klotho gene was contributed with calcium metabolisms, and glucose metabolisms. Therfore we used female klotho mouse as primary study of the action that the low dose-rate irradiation gave to lifespan prolongation effects, and measured glucose and insulin level in the blood. We also measured the level of TNF-alpha as one of the inflammation marker.
The kloho mice irradiated from 28 days old at a source of gamma ray (137Cs). The level of TNF-alpha in blood of the irradiated group decreased after the longer irradiation. This result was thought the inflammation was suppressed by the irradiation. The glucose level in the irradiated group was decreased and the insulin level didn't change the longer irradiation. On the other hand, the level of glucose didn't change, and the insulin level was decreased in the non-irradiated control group. These results might be suggested that the enhancement of pancreatic antioxidants protected oxygen damages.
We thought that the prolongation effect of lifespan of klotho mouse by the irradiation might be not only the suppression of inflammation, but also increase in antioxidants, and controlled calcium metabolisms.
