后代小鼠的世代低剂量率137C内部暴露的影响
Effects of generational low dose-rate 137Cs internal exposure in descendant mice
影响因子:2.40000
分区:医学4区 / 核科学技术3区 生物学4区 核医学4区
发表日期:2024
作者:
Hiroo Nakajima, Mizuki Ohno, Kazuko Uno, Satoru Endo, Masatoshi Suzuki, Hiroshi Toki, Tadashi Saito
摘要
为了定量研究慢性低剂量内部暴露于137的影响对多代DNA损伤，致癌性和后代的影响。根据下一代鼠突变率预测人类的潜在遗传风险，以确认食物当前剖宫产137剂量限制的合理性。在饮用水中向A/J小鼠提供了Cesium-137（100 bq/ml），从25代超过25代（G25）促进了慢性，低剂量，低剂量的内部暴露（G25）。将A/J小鼠与具有相同起源祖先（无剖宫产137水）的对照菌株进行了比较，以进行DNA双链断裂（DSB），氧化应激，染色体像畸变，微核测试结果，全基因组分析，致癌性，肿瘤生长率和免疫能力。与对照组相比，剖宫产137组的DNA DSB和氧化应激显着增加。但是，两组之间在染色体畸变，微核或整个基因组序列突变分析方面没有观察到显着差异。尽管两组之间的致癌率没有差异，但剖宫产137组的肿瘤生长速率得到了显着抑制。 Cesium-137组的抗肿瘤细胞因子趋势可能导致了这种作用。在G25后饮用含有100 bq/ml剖宫产的小鼠的后代，未观察到病理或遗传作用。低剂量辐射对致癌性的贡献不是加性的，而是抑制生长。尽管负面数据不是结论性的，但这些发现被认为是高度可靠的。
Abstract
To quantitatively investigate the effects of chronic low-dose internal exposure to Cesium-137 on DNA damage, carcinogenicity, and offspring over multiple generations. The potential genetic risk in humans was predicted based on next-generation murine mutation rates to confirm the reasonableness of the current Cesium-137 dose limits for food. Cesium-137 (100 Bq/mL) was provided in drinking water to A/J mice, facilitating chronic, low-dose, low-dose-rate internal exposure through sibling mating over 25 generations (G25). The A/J mice were compared with a control strain with the same origin ancestry (no Cesium-137 water) for DNA double-strand breaks (DSBs), oxidative stress, chromosome aberrations, micronucleus test results, whole genome analysis, carcinogenicity, tumor growth rate, and immune competence. Compared to the control group, DNA DSBs and oxidative stress were significantly increased in the Cesium-137 group. However, no significant differences were observed between the groups regarding chromosome aberration, micronuclei, or the whole genome sequence mutation analysis. Although the carcinogenic rate did not differ between the groups, the rate of tumor growth was significantly suppressed in the Cesium-137 group. The anti-tumor cytokine trend in the Cesium-137 group likely contributed to this effect. No pathological or genetic effects were observed in the offspring of mice drinking water containing 100 Bq/mL Cesium-137 after G25. The contribution of low dose-rate radiation to carcinogenicity was not additive but growth-inhibitory. Although the negative data are not conclusive, these findings are deemed highly reliable.