Formation of an oxidative DNA damage, 8-hydroxydeoxyguanosine, in mouse lung DNA after intratracheal instillation of diesel exhaust particles and effects of high dietary fat and beta-carotene on this process.
Formation of an oxidative DNA damage, 8-hydroxydeoxyguanosine, in mouse lung DNA after intratracheal instillation of diesel exhaust particles and effects of high dietary fat and beta-carotene on this process.
复制标题
气管内滴注柴油尾气颗粒后，小鼠肺 DNA 中形成氧化性 DNA 损伤 8-羟基脱氧鸟苷，以及高膳食脂肪和 β-胡萝卜素对此过程的影响。
作者：
Makoto Nagashima;H. Kasai;J. Yokota;Y. Nagamachi;T. Ichinose;M. Sagai
柴油机尾气颗粒（DEP）会导致实验动物呼吸道肿瘤。先前的研究表明，DEP 会产生超氧化物和羟基自由基。为了检查氧自由基是否参与 DEP 诱导的小鼠肺部肿瘤发生，研究了 DEP 形成的氧化性 DNA 损伤 8-羟基脱氧鸟苷 (oh8dG)。此外，还研究了高膳食脂肪和β-胡萝卜素在此过程中的作用。气管内滴注 DEP 后，观察到小鼠肺 DNA 中 oh8dG 显着增加。高膳食脂肪促进了肺 DNA 中 oh8dG 的形成。 β-胡萝卜素的摄入抑制了肺 DNA 中 oh8dG 的形成，但 β-胡萝卜素对这一过程的保护作用并不具有统计学意义。这些结果表明，肺 DNA 中 oh8dG 的形成是由 DEP 产生的氧自由基诱导的。因此，oh8dG 可能是 DEP 诱导的小鼠肺部肿瘤发生中的一种促突变损伤，并且高膳食脂肪通过在小鼠肺 DNA 中生成 oh8dG 来增强这一过程。
Diesel exhaust particles (DEP) cause tumors in the respiratory tracts of experimental animals. It was previously shown that DEP produced superoxide and hydroxyl radical. To examine whether oxygen radicals are involved in mouse lung tumorigenesis induced by DEP, formation of an oxidative DNA damage, 8-hydroxydeoxyguanosine (oh8dG), by DEP was investigated. Furthermore, the role of high dietary fat and beta-carotene on this process was studied. After intratracheal instillation of DEP, a significant increase of oh8dG in mouse lung DNA was observed. High dietary fat enhanced the formation of oh8dG in lung DNA. Intake of beta-carotene suppressed the formation of oh8dG in lung DNA, but the protective effect of beta-carotene against this process was not statistically significant. These results suggest that formation of oh8dG in lung DNA was induced by oxygen free radicals produced by DEP. Thus, it is possible that oh8dG is a promutagenic lesion in DEP-induced lung tumorigenesis in mice and high dietary fat enhances this process through the generation of oh8dG in mouse lung DNA.