The School of Public Health, Guangxi Medical University, Nanning, Guangxi 530021, PR China.
Toxicology. 2012 Aug 16;298(1-3):24-9. doi: 10.1016/j.tox.2012.04.009. Epub 2012 Apr 26.
Chemical contaminants, such as benzo[a]pyrene (B[a]P), may modulate transcriptional responses in cells via the activation of aryl hydrocarbon receptor (AhR) or through responses to DNA damage following adduct formation. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy can be employed in a non-destructive fashion to interrogate the biochemical signature of cells via generation of infrared (IR) spectra. By applying to generated spectral datasets subsequent computational approaches such as principal component analysis plus linear discriminant analysis (PCA-LDA), derived data reduction is achieved to facilitate the visualization of wavenumber-related alterations in target cells. Discriminating spectral variables might be associated with lipid or glycogen content, conformational protein changes and phosphorylation, and structural alterations in DNA/RNA. Using this approach, we investigated the dose-related effects of B[a]P in MCF-7 cells concentrated in S- or G₀/G₁-phase. Our findings identified that in PCA-LDA scores plots a clear segregation of IR spectra was evident, with the major spectral alterations associated with DNA/RNA, secondary protein structure and lipid. Dose-related effects were observed and even with exposures as low as 10⁻⁹ M B[a]P, significant (P ≤ 0.001) separation of B[a]P-treated vs. vehicle control cells was noted. ATR-FTIR spectroscopy with computational analysis is a novel approach to identify the effects of environmental contaminants in target cells.
化学污染物，如苯并[a]芘（B[a]P），可能通过激活芳烃受体（AhR）或通过形成加合物后对 DNA 损伤的反应，来调节细胞中的转录反应。衰减全反射傅里叶变换红外（ATR-FTIR）光谱可以以非破坏性的方式通过生成红外（IR）光谱来询问细胞的生化特征。通过对生成的光谱数据集应用后续的计算方法，如主成分分析加线性判别分析（PCA-LDA），可以实现数据减少，以促进目标细胞中与波数相关的变化的可视化。区分光谱变量可能与脂质或糖原含量、构象蛋白变化和磷酸化以及 DNA/RNA 的结构变化有关。使用这种方法，我们研究了 B[a]P 在 MCF-7 细胞中的剂量相关效应，这些细胞集中在 S 期或 G0/G1 期。我们的研究结果表明，在 PCA-LDA 得分图中，IR 光谱的明显分离是显而易见的，主要的光谱变化与 DNA/RNA、二级蛋白质结构和脂质有关。观察到剂量相关的效应，甚至在暴露于低至 10⁻⁹ M 的 B[a]P 时，也注意到 B[a]P 处理的细胞与载体对照细胞之间有显著的（P ≤ 0.001）分离。ATR-FTIR 光谱与计算分析是一种识别环境污染物对靶细胞影响的新方法。
