Department of Nanotoxicology and Molecular Epidemiology, Institute of Experimental Medicine of the Czech Academy of Sciences, 14220 Prague, Czech Republic.
Department of Genetic Toxicology and Epigenetics, Institute of Experimental Medicine of the Czech Academy of Sciences, 14220 Prague, Czech Republic.
Int J Mol Sci. 2020 Jul 4;21(13):4763. doi: 10.3390/ijms21134763.
This study presents a toxicological evaluation of two types of carbon dots (CD), similar in size (<10 nm) but differing in surface charge. Whole-genome mRNA and miRNA expression (RNAseq), as well as gene-specific DNA methylation changes, were analyzed in human embryonic lung fibroblasts (HEL 12469) after 4 h and 24 h exposure to concentrations of 10 and 50 µg/mL (for positive charged CD; pCD) or 10 and 100 µg/mL (for negative charged CD, nCD). The results showed a distinct response for the tested nanomaterials (NMs). The exposure to pCD induced the expression of a substantially lower number of mRNAs than those to nCD, with few commonly differentially expressed genes between the two CDs. For both CDs, the number of deregulated mRNAs increased with the dose and exposure time. The pathway analysis revealed a deregulation of processes associated with immune response, tumorigenesis and cell cycle regulation, after exposure to pCD. For nCD treatment, pathways relating to cell proliferation, apoptosis, oxidative stress, gene expression, and cycle regulation were detected. The expression of miRNAs followed a similar pattern: more pronounced changes after nCD exposure and few commonly differentially expressed miRNAs between the two CDs. For both CDs the pathway analysis based on miRNA-mRNA interactions, showed a deregulation of cancer-related pathways, immune processes and processes involved in extracellular matrix interactions. DNA methylation was not affected by exposure to any of the two CDs. In summary, although the tested CDs induced distinct responses on the level of mRNA and miRNA expression, pathway analyses revealed a potential common biological impact of both NMs independent of their surface charge.
本研究对两种类型的碳点（CD）进行了毒理学评价，这两种 CD 在尺寸（<10nm）上相似，但表面电荷不同。在暴露于浓度为 10 和 50μg/ml（正电荷 CD；pCD）或 10 和 100μg/ml（负电荷 CD，nCD）的条件下，对人类胚胎肺成纤维细胞（HEL 12469）进行了 4 小时和 24 小时处理后，分析了全基因组 mRNA 和 miRNA 表达（RNAseq）以及基因特异性 DNA 甲基化变化。结果表明，测试的纳米材料（NMs）表现出明显不同的反应。与 nCD 相比，pCD 的暴露诱导表达的 mRNA 数量要少得多，两种 CD 之间共同差异表达的基因很少。对于两种 CD，随着剂量和暴露时间的增加，失调的 mRNA 数量增加。通路分析显示，pCD 暴露后，与免疫反应、肿瘤发生和细胞周期调节相关的过程被下调。对于 nCD 处理，检测到与细胞增殖、细胞凋亡、氧化应激、基因表达和周期调节相关的途径。miRNA 的表达也呈现出类似的模式：nCD 暴露后变化更为明显，两种 CD 之间共同差异表达的 miRNA 很少。基于 miRNA-mRNA 相互作用的通路分析显示，两种 CD 均下调了与癌症相关的通路、免疫过程和细胞外基质相互作用过程。DNA 甲基化不受两种 CD 暴露的影响。总之，尽管测试的 CDs 在 mRNA 和 miRNA 表达水平上引起了不同的反应，但通路分析显示，两种 NM 具有潜在的共同生物学影响，而与它们的表面电荷无关。
