Abstract
The response of biological systems to various types of radiations have many ambiguous dimensions. Among ionizing radiations, in vitro external gamma radiation therapy has mostly studied as model to declare the biological system challenges with radiation effects. Cell/organism exposure to gamma radiation, caused cascade of ionization events such as severe irreversible biological damages. However, the biological responses and oxidative stress related mechanisms under acute radiation conditions poorly understood in inflammatory systems. Following study tried to give a model about ionizing radiation effect on the macrophage that had a key role in inflammation mechanisms; to evaluate the impact of radiotherapy approach for inflammatory disease as rheumatoid arthritis. To this aim, Macrophage cell line (RAW 264.7) culture, exposed to different doses of gamma radiation (0,4, 6, 8, 10 Gy). Cell viability, apoptosis, cell cycle, migration; NO and PGE2 production; expression of pro-inflammatory and apoptotic genes and cytokine secretion of macrophages was also evaluated.The results showed that gamma treatment, at 4 Gy radiation, have slight effect on macrophage characteristics and cytokine secretion pattern. Versus, higher doses (8 and 10 Gy) increased DNA damage, expression of apoptotic genes and secretion of NO and PGE2 cytokines. 6 Gy radiation, the maximum radiation dose, show moderate nondestructive effects and inflammation process modulation. In this study, doses higher than 6 Gy of Gamma radiation caused cell mortality. It seems that 6 Gy Gamma radiation modulate the inflammatory cascade caused by macrophage cell, as a central core of autoimmune inflammatory disease in acute dose radiation therapy.