Ramachandran Rajan, Krishnaraj Chandran, Kumar V K Abhay, Harper Stacey L, Kalaichelvan Thangavelu P, Yun Soon-Il
1Centre for Advanced Studies in Botany, School of Life Sciences, University of Madras, Guindy Campus, Chennai, Tamil Nadu 600 025 India.
2Department of Food Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, Jeonju, 561-756 Republic of Korea.
3 Biotech. 2018 Oct;8(10):441. doi: 10.1007/s13205-018-1457-y. Epub 2018 Oct 5.
In this study, toxicity of biologically synthesized silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) was compared using zebrafish as a model organism. At 96 h, LC of AgNPs and AuNPs was found to be 24.5 µg/L and 41 mg/L, respectively. Following the LC determination, half of the LC of AgNPs (12.25 µg/L) and AuNPs (20.5 mg/L) was exposed to adult zebrafishes for 14 days. Morphological changes, liver marker enzymes, reactive oxygen species (ROS) generation, genotoxic effects and mRNA expression levels of oxidative stress and innate immune response related genes were studied using nanoparticle treated gill, liver and blood cells. In this study, AgNP-treated gill and liver tissues showed a number of morphological changes such as cell membrane damage, irregular cell outlines, pyknotic nuclei and complete disruption of gill and liver cells; on the contrary, AuNPs treated liver tissues alone showed such changes. The levels of liver marker enzymes such as alanine aminotransferase and aspartate aminotransferase were increased after AgNPs treatment when compared to AuNPs treatment. AgNP-treated liver cells showed higher levels of ROS generation than the control; on the other hand, AuNPs treatment exhibited lower levels of ROS generation than the control. Interestingly, AgNP-treated blood cells showed micronuclei formation and nuclear abnormalities, while AuNPs treatment did not show such effects. Based on these observations, it is clear that AgNPs may cause oxidative stress and immunotoxicity to adult zebrafish than the AuNPs. However, these results clearly reveal the significance of relatively safe and less toxic bionanomaterials for possible biomedical applications.
在本研究中，以斑马鱼作为模式生物，比较了生物合成的银纳米颗粒（AgNPs）和金纳米颗粒（AuNPs）的毒性。在96小时时，发现AgNPs和AuNPs的半数致死浓度（LC）分别为24.5μg/L和41mg/L。在确定LC之后，将AgNPs（12.25μg/L）和AuNPs（20.5mg/L）半数致死浓度的一半暴露于成年斑马鱼14天。使用纳米颗粒处理过的鳃、肝脏和血细胞，研究了形态变化、肝脏标记酶、活性氧（ROS）生成、遗传毒性效应以及氧化应激和先天免疫反应相关基因的mRNA表达水平。在本研究中，AgNP处理的鳃和肝脏组织出现了许多形态变化，如细胞膜损伤、细胞轮廓不规则、细胞核固缩以及鳃和肝细胞的完全破坏；相反，仅AuNPs处理的肝脏组织出现了这些变化。与AuNPs处理相比，AgNPs处理后丙氨酸转氨酶和天冬氨酸转氨酶等肝脏标记酶的水平升高。AgNP处理的肝细胞显示出比对照组更高的ROS生成水平；另一方面，AuNPs处理显示出比对照组更低的ROS生成水平。有趣的是，AgNP处理的血细胞出现了微核形成和核异常，而AuNPs处理未显示出此类效应。基于这些观察结果，很明显AgNPs对成年斑马鱼可能比AuNPs造成氧化应激和免疫毒性。然而，这些结果清楚地揭示了相对安全且毒性较小的生物纳米材料在可能的生物医学应用中的重要性。
