基于拉曼光谱的铅致肝细胞生物分子变化研究

利用拉曼光谱技术采集不同铅离子暴露时间(0.5,1.5,3,6,12,24h)、暴露浓度(0.05,0.1,0.5,1,5mg/L)下HepG2细胞的光谱数据,欲探究在不同铅暴露条件下肝细胞的分子变化及其相关机制.研究结果发现,在不同条件下各组细胞的光谱形态基本相同,但部分特征峰的吸光度强度存在差异.经多元统计分析发现,除6h外,同一暴露时间下不同暴露浓度细胞的光谱数据在LD1上均存在离散趋势,并在暴露24h时最明显.细胞内蛋白质、脂质、核酸、类胡萝卜素、碳水化合物等生物分子的特征峰表现出明显差异,但不同类型生物分子发生显著变化的时间并不相同.由此可见铅暴露可损伤肝细胞蛋白质、脂质、核酸、类胡萝卜素的结构并影响其正常功能,这种毒性效应呈剂量-效应关系,且随暴露时间的增加而增加.本研究说明拉曼光谱可以实现铅对肝细胞生物分子变化的相关检测,这不仅为之后的细胞毒理研究提供了新的思路,同时也为环境污染物的安全评价提供了理论依据.

Lead-induced alterations in hepatocyte biomolecules based on Raman spectroscopy

In this study, we employed Raman spectroscopy to explore the bio-molecular alterations in HepG2cells following exposure to lead with concentrations of 0.05, 0.1, 0.5, 1, 5mg/L, which took different time periods (0.5, 1.5, 3, 6, 12, 24h) respectively. Raman spectra correlated to cellular biological information was collected via Raman microscopy to further investigate the bio-molecular alterations of liver cells community following lead exposure. It showed that although the spectra in each treatment group were similar, certain diversities of the peaks positions and the absorption intensities were observed. Additionally, multivariate analysis was applied to the spectral dataset to determine the biological changes underlying the exposure, and it showed that the spectral data of cellular groups following exposures at different concentrations with the same exposure time showed a discrete trend on LD1, and it was significantly observed in 24-h exposure. The results, as well, indicated that lead exposure can damage the structure of liver cell proteins, lipids, nucleic acids, carotenoids, carbohydrates and affect their normal functions. These cellular responses are dose-related and increases with exposure time. In conclusion, our study suggests that Raman spectroscopy is proper tool with ability to detect the biological molecular changes in liver cells following lead exposure. It can not only provide a new assay in toxicology research, but also provides a theoretical basis for rapid safety evaluation of environmental pollutants.