Almeida Idália, Martins Filipa, Goodfellow Brian J, Nunes Alexandra, Rebelo Sandra
Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal.
CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Int J Mol Sci. 2025 Aug 20;26(16):8027. doi: 10.3390/ijms26168027.
Neuronal differentiation is a highly dynamic process marked by coordinated biochemical, structural, and metabolic changes. Rat primary cortical neurons are the preferred cell model to study this process as they can maintain their functional attributes, including functional synapses, and simulate the behavior of neuronal cells in vivo. In this study, we employed Fourier transform infrared (FTIR) spectroscopy to monitor the molecular transformations that occur during the differentiation of rat cortical neurons. Partial least squares regression (PLS-R) analysis from the 1800-1500 cm region further allows the identification of the spectroscopic profile of early and late differentiation stages, highlighting the technique's ability to detect subtle molecular changes. Further peak intensity analysis revealed significant changes in the cells' metabolome during differentiation; it was possible to observe remodeling of protein secondary structures and an increase in protein phosphorylation levels, which can imply activation of signaling pathways essential for neuronal differentiation and maturation. Concomitantly, lipid-associated spectral regions demonstrated increased levels of total lipids, lipid esters, and longer acyl chains and decreased unsaturation levels, alterations that can be linked to membrane expansion throughout neuronal differentiation. These findings underscore FTIR spectroscopy as a valuable tool for studying neuronal differentiation, offering insights into the conformational and metabolic shifts underlying the formation of mature neuronal phenotypes.
神经元分化是一个高度动态的过程，其特征是生化、结构和代谢变化相互协调。大鼠原代皮质神经元是研究这一过程的首选细胞模型，因为它们能够维持其功能特性，包括功能性突触，并模拟体内神经元细胞的行为。在本研究中，我们采用傅里叶变换红外（FTIR）光谱法来监测大鼠皮质神经元分化过程中发生的分子转变。对1800 - 1500 cm区域进行偏最小二乘回归（PLS - R）分析，进一步能够识别早期和晚期分化阶段的光谱特征，突出了该技术检测细微分子变化的能力。进一步的峰强度分析揭示了分化过程中细胞代谢组的显著变化；能够观察到蛋白质二级结构的重塑以及蛋白质磷酸化水平的增加，这可能意味着对神经元分化和成熟至关重要的信号通路被激活。同时，与脂质相关的光谱区域显示总脂质、脂质酯和较长酰基链的水平增加，不饱和水平降低，这些变化可能与神经元分化过程中的膜扩张有关。这些发现强调了FTIR光谱法作为研究神经元分化的一种有价值工具，为成熟神经元表型形成背后的构象和代谢变化提供了见解。
