Zinc oxide (ZnO) nanoparticles (NPs) have potential applications in cosmetics, food packaging and biomedicine but concerns regarding their safety need to be addressed. In the present study, the immunotoxic potential of ZnO NPs was evaluated in different ages of BALB/c mice after sub-acute exposure. The cytokine release, immunophenotyping, distribution of ZnO NPs and ultrastructural changes were assessed. A significant (p < 0.05) change in the CD4- and CD8-cells, levels of IL-6, IFN-γ and TNF-α and reactive oxygen species were observed in aged mice. In juvenile mice, increase in reactive oxygen species and IL-6 and TNF-α levels was observed with no significant changes in adult mice. A significant (p < 0.05) increase in the expression levels of mitogen activated protein kinase (MAPK) cascade proteins such as phospho-ERK1/2, phospho-JNK and phospho-p38 were also induced in aged mice. Collectively, our results indicate that the aged mice are more susceptible to ZnO NP induced immunotoxicity.

中文翻译：

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氧化锌纳米颗粒在BALB / c小鼠中诱导了年龄依赖性免疫毒性。

氧化锌（ZnO）纳米颗粒（NPs）在化妆品，食品包装和生物医学中具有潜在的应用，但需要解决对其安全性的担忧。在本研究中，评估了亚急性暴露后不同年龄的BALB / c小鼠中ZnO NPs的免疫毒性潜力。评估细胞因子释放，免疫表型，ZnO NPs的分布和超微结构的变化。在老年小鼠中观察到CD4-和CD8-细胞，IL-6，IFN-γ和TNF-α的水平以及活性氧的显着变化（p <0.05）。在幼年小鼠中，观察到活性氧和IL-6和TNF-α含量增加，成年小鼠没有明显变化。促分裂原活化蛋白激酶（MAPK）级联蛋白（例如磷酸化ERK1 / 2）的表达水平显着提高（p <0.05），在老年小鼠中也诱导了磷酸化JNK和磷酸化p38。总体而言，我们的结果表明，老年小鼠对ZnO NP诱导的免疫毒性更敏感。