Perera Palalle G Tharushi, Vongsvivut Jitraporn, Linklater Denver, Vilagosh Zoltan, Appadoo Dominique, Nguyen The Hong Phong, Tobin Mark J, Croft Rodney, Ivanova Elena P
School of Science, RMIT University, 2476, Melbourne, Victoria 3001, Australia.
IR Microspectroscopy (IRM) Beamline, ANSTO-Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168, Australia.
J Synchrotron Radiat. 2025 Jan 1;32(Pt 1):155-161. doi: 10.1107/S1600577524010944.
Synchrotron sourced Fourier transform infrared (SS FTIR) microspectroscopy was employed to investigate the biological effects on the neuron-like pheochromocytoma (PC 12) cells after exposure to synchrotron sourced terahertz (SS THz) radiation. Over 10 min of exposure, the PC 12 cells received a total energy of 600 J m, with a total incident power density of ∼1.0 W m (0.10 mW cm) at the beam extraction port (BEP) of the THz beamline at the Australian Synchrotron. To investigate the metabolic response of PC 12 cells after synchrotron THz radiation exposure, we utilized the FTIR microscope at the Infrared Microspectroscopy IRM beamline, which offers high photon flux and diffraction-limited spatial resolution enabling the detection of functional group variations in biological molecules at a single-cell level. Principal component analysis (PCA) based on the SS FTIR spectral data revealed a distinct separation of SS THz-exposed and control (non-exposed) cells. According to the PCA loadings, the key changes in the exposed cells involved lipid and protein compositions as indicated by the stretching vibrations of CH/CH groups and amide I/II bands, respectively. An increase in lipids, such as cholesterol, or notable changes in their compositions and in some protein secondary structures were observed in the SS THz-exposed cells. The PCA analysis further suggests that PC 12 cells might maintain cell membrane stability after SS THz irradiation through higher volumes of cholesterol and cell morphology via regulation of the synthesis of cytoskeleton proteins such as actin-related proteins. The outcome of this study re-emphasized the exceptional SS FTIR capability to perform single-cell analysis directly, providing (i) unique biological information on cell variability within the population as well as between different groups, and (ii) evidence of molecular changes in the exposed cells that could lead to a deeper understanding of the effect of THz exposure at a single-cell level.
同步辐射源傅里叶变换红外（SS FTIR）显微光谱技术被用于研究神经元样嗜铬细胞瘤（PC 12）细胞在暴露于同步辐射源太赫兹（SS THz）辐射后的生物学效应。在超过10分钟的暴露过程中，PC 12细胞接收的总能量为600 J m，在澳大利亚同步加速器太赫兹光束线的束流引出端口（BEP）处的总入射功率密度约为1.0 W m（0.10 mW cm）。为了研究同步辐射太赫兹辐射暴露后PC 12细胞的代谢反应，我们利用了红外显微光谱（IRM）光束线的傅里叶变换红外显微镜，该显微镜具有高光子通量和衍射极限空间分辨率，能够在单细胞水平检测生物分子中的官能团变化。基于SS FTIR光谱数据的主成分分析（PCA）显示，暴露于SS THz的细胞和对照（未暴露）细胞有明显分离。根据PCA载荷，暴露细胞中的关键变化分别涉及脂质和蛋白质组成，如CH/CH基团的伸缩振动和酰胺I/II带所示。在暴露于SS THz的细胞中观察到脂质（如胆固醇）增加，或其组成和一些蛋白质二级结构发生显著变化。PCA分析进一步表明，PC 12细胞可能通过增加胆固醇含量来维持细胞膜稳定性，并通过调节肌动蛋白相关蛋白等细胞骨架蛋白的合成来维持细胞形态。这项研究的结果再次强调了SS FTIR直接进行单细胞分析的卓越能力，提供了（i）关于群体内以及不同组之间细胞变异性的独特生物学信息，以及（ii）暴露细胞中分子变化的证据，这有助于在单细胞水平更深入地理解太赫兹暴露的影响。
