Zhang Zhimin, Li Jingkang, Ma Mo, Shi Hui, Lu Meijun, Liang Fanghui, Wang Xinghua, Ma Pinyi, Tian Yuan, Song Daqian, Zhang Ziwei
College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun, 130012, China; Department of Pharmacy, Changchun Medical College, Changchun, 130031, China.
College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun, 130012, China.
Talanta. 2025 Apr 1;285:127378. doi: 10.1016/j.talanta.2024.127378. Epub 2024 Dec 14.
Non-alcoholic fatty liver disease (NAFLD) now affects more than one quarter of the global population and becomes a heavy public health burden. However, the underlying mechanism for the pathogenesis of NAFLD is still not clear. Carboxylesterase 2 (CES2), highly abundant in the liver and intestine, plays an important role in endogenous lipid metabolism and lipolysis. So far, the literatures for the role of CES2 in the development of NAFLD are still limited. In this study, we designed and synthesized a near-infrared fluorescent probe (HP-LZ-CES2) which can be specifically recognized and hydrolyzed by CES2, releasing a benzoate residue and a fluorophore (HP-LZ) with good fluorescence signal. With this probe, CES2 levels can be quantitatively measured in vitro and qualitatively visualized in living cells and mice. The probe has the advantages of large Stokes shift, high detection sensitivity and good selectivity. Further, the CES2 expression levels were visually investigated in both high-fat cells as the in vitro model for NAFLD and high-fat diet fed mouse as the in vivo model for NAFLD. The cell imaging experiments indicated a reduction of fluorescence signal in high-fat hepatic cells. The in vivo experiments showed an obvious reduction of fluorescence in the liver of NAFLD mouse model, which is consistent with the hepatic cell experiments. In contrast, an enhancement of fluorescence was observed in the intestine of NAFLD mouse model. As a result, the NAFLD mouse model can be visually distinguished from the normal chow mouse by vision. Therefore, the proposed probe can be an auxiliary tool for the diagnosis of NAFLD and a visual tool for understanding CES2's role in the development of NAFLD.
非酒精性脂肪性肝病（NAFLD）目前影响着全球超过四分之一的人口，成为沉重的公共卫生负担。然而，NAFLD发病机制的潜在机制仍不清楚。羧酸酯酶2（CES2）在肝脏和肠道中高度丰富，在内源性脂质代谢和脂肪分解中起重要作用。到目前为止，关于CES2在NAFLD发展中作用的文献仍然有限。在本研究中，我们设计并合成了一种近红外荧光探针（HP-LZ-CES2），它可以被CES2特异性识别并水解，释放出具有良好荧光信号的苯甲酸酯残基和荧光团（HP-LZ）。利用该探针，可以在体外定量测量CES2水平，并在活细胞和小鼠体内进行定性可视化。该探针具有斯托克斯位移大、检测灵敏度高和选择性好的优点。此外，在作为NAFLD体外模型的高脂细胞和作为NAFLD体内模型的高脂饮食喂养小鼠中，对CES2表达水平进行了可视化研究。细胞成像实验表明高脂肝细胞中的荧光信号降低。体内实验显示NAFLD小鼠模型肝脏中的荧光明显降低，这与肝细胞实验结果一致。相反，在NAFLD小鼠模型的肠道中观察到荧光增强。因此，通过视觉可以将NAFLD小鼠模型与正常饮食小鼠区分开来。因此，所提出的探针可以作为NAFLD诊断的辅助工具以及了解CES2在NAFLD发展中作用的可视化工具。
