Peng Qiyun, Dong Yingfu, Chen Yecang, Glidle Andrew, Kong Lingjiang, Yin Huabing, Xu Jiabao, Yang Kun
School of Information and Communication Engineering, University of Electronic Science and Technology of China, Chengdu, People's Republic of China; Division of Biomedical Engineering, James Watt School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, People's Republic of China.
Talanta. 2024 Sep 1;277:126389. doi: 10.1016/j.talanta.2024.126389. Epub 2024 Jun 6.
Ammonia is a prevalent aquatic pollutant that disrupts cellular functions and energy metabolism in fish, posing significant environmental and health threats. This research investigates the critical role of arginase 2 (ARG2) in mitigating ammonia toxicity in fish cells and its implications in adapting to nitrogen metabolism under high ammonia exposure. Through a CRISPR-Cas9 engineered ARG2 knockdown (KD) in the Epithelioma Papulosum Cyprini (EPC) cell line, we first investigated the biochemical responses of ARG2 KD and wild-type (WT) EPC cells to ammonia stress (NHCl treatment), showing diminished urea production and decreased cell viability in ARG2 KD cells. Subsequently, single-cell Raman spectroscopy analysis revealed that ARG2 KD cells exhibited profound metabolic shifts, including changes in protein, nucleic acids, lipid and sugar levels, showing the adjusting role of ARG2 in the balance of carbohydrate and nitrogen metabolism. Furthermore, the upregulated responses of various amino acids, such as glutamine, arginine, alanine, glutamic acid, glycine, histidine, phenylalanine and valine, in WT cells after NHCl treatment diminished in ARG2 KD cells except for the decrease in aspartic acid, indicating a switching effect of ARG2 in nitrogen metabolism under ammonia stress. This study highlights ARG2's essential role in ammonia detoxification and emphasizes ARG2's protective function and its importance in metabolism, shedding light on the adaptive mechanisms fish cells deploy against high ammonia environments. These insights contribute to deep understanding of aquatic organisms' molecular responses to environmental ammonia pollution, offering potential strategies for their protection.
氨是一种常见的水生污染物，会扰乱鱼类的细胞功能和能量代谢，对环境和健康构成重大威胁。本研究调查了精氨酸酶2（ARG2）在减轻鱼类细胞氨毒性中的关键作用及其在高氨暴露下适应氮代谢的意义。通过在鲤上皮瘤（EPC）细胞系中利用CRISPR-Cas9技术构建精氨酸酶2基因敲低（KD）模型，我们首先研究了精氨酸酶2基因敲低细胞和野生型（WT）EPC细胞对氨胁迫（氯化铵处理）的生化反应，结果显示精氨酸酶2基因敲低细胞中尿素生成减少，细胞活力下降。随后，单细胞拉曼光谱分析表明，精氨酸酶2基因敲低细胞表现出深刻的代谢变化，包括蛋白质、核酸、脂质和糖水平的改变，这表明精氨酸酶2在碳水化合物和氮代谢平衡中具有调节作用。此外，氯化铵处理后野生型细胞中各种氨基酸（如谷氨酰胺、精氨酸、丙氨酸、谷氨酸、甘氨酸、组氨酸、苯丙氨酸和缬氨酸）的上调反应在精氨酸酶2基因敲低细胞中减弱，但天冬氨酸减少除外，这表明在氨胁迫下精氨酸酶2在氮代谢中具有转换作用。本研究突出了精氨酸酶2在氨解毒中的重要作用，并强调了精氨酸酶2的保护功能及其在代谢中的重要性，揭示了鱼类细胞应对高氨环境的适应性机制。这些见解有助于深入了解水生生物对环境氨污染的分子反应，为其保护提供潜在策略。
