Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 405 N Mathews Ave, Urbana, Illinois 61801, United States.
Anal Chem. 2020 Dec 15;92(24):15943-15952. doi: 10.1021/acs.analchem.0c03366. Epub 2020 Nov 24.
The metabolic properties of live cells are very susceptible to intra- or extracellular perturbations, making their measurements challenging tasks. We show that the dynamics of lipid droplets (LDs) carry information to measure the lipid metabolism of live cells. Coherent anti-Stokes Raman scattering microscopy was used to statistically quantify LD dynamics in living cells in a label-free manner. We introduce dynamic signatures of cells derived from the LD displacement, speed, travel length, and directionality, which allows for the detection of cellular changes induced by stimuli such as fluorescent labeling, temperature change, starvation, and chemical treatment. Histogram fittings of the dynamic signatures using log-normal distribution functions provide quantification of changes in cellular metabolic states. The LD dynamics also enable separation of subpopulations of LDs correlated with different functions. We demonstrate that LD dynamics measured by chemical imaging are new markers to quantify the metabolic changes in live cells.
活细胞的代谢特性非常容易受到细胞内外的干扰，因此对其进行测量是一项具有挑战性的任务。我们发现，脂滴（LDs）的动力学可以提供活细胞脂质代谢的测量信息。我们使用相干反斯托克斯拉曼散射显微镜（CARS）以无标记的方式对活细胞中的 LD 动力学进行了统计学量化。我们引入了源自 LD 位移、速度、行程长度和方向的细胞动力学特征，这些特征可用于检测由荧光标记、温度变化、饥饿和化学处理等刺激引起的细胞变化。使用对数正态分布函数对动力学特征进行直方图拟合，可提供细胞代谢状态变化的定量评估。LD 动力学还可以分离与不同功能相关的 LD 亚群。我们证明，通过化学成像测量的 LD 动力学是量化活细胞代谢变化的新标志物。
