Hypothermia is directly linked to metabolism; however, it is still unknown how the overall metabolism is altered by oral administration of hypothermic agent, l-citrulline (l-Cit). The present study aimed to determine the characteristics of liver metabolites of chicks orally administered l-Cit to provide a greater understanding of its metabolism. Capillary electrophoresis–time-of-flight mass spectrometry (CE-TOFMS) and liquid chromatography–time-of-flight mass spectrometry (LC-TOFMS) were conducted on liver samples after oral administration of l-Cit. A total of 361 liver metabolites were identified. Although a small number of samples were used for each group, a principal component analysis and heatmap patterns confirmed that the composition of metabolites could be segregated from each other. Of the 361 compounds detected in the liver, 41 compounds, including amino acids related to the Cit-arginine (Arg) cycle, argininosuccinic acid, Arg, ornithine, and Cit, as well as gamma aminobutyric acid, glycine, histidine, and nicotinamide adenine dinucleotide were abundant in l-Cit-treated livers. In contrast, 24 compounds containing fatty acids, amino acids, and cyclic adenosine monophosphate were lower in the l-Cit group. These data imply that the active Cit-Arg cycle, TCA cycle metabolism, and a low activity in fatty acid metabolism occur in l-Cit-treated broiler chicks.

中文翻译：

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肉鸡肝脏代谢组学分析：口服 l-瓜氨酸后的代谢物分析

体温过低与新陈代谢直接相关；然而，口服降温剂l -瓜氨酸 ( l -Cit) 如何改变整体代谢仍是未知数。本研究旨在确定口服l -Cit的小鸡肝脏代谢物的特征，以更好地了解其代谢。毛细管电泳-飞行时间质谱法 (CE-TOFMS) 和液相色谱-飞行时间质谱法 (LC-TOFMS) 在口服 l 后对肝脏样本进行了分析-引用。共鉴定出 361 种肝脏代谢物。尽管每组使用少量样品，但主成分分析和热图模式证实代谢物的组成可以相互分离。在肝脏中检测到的 361 种化合物中，41 种化合物包括与胞嘧啶-精氨酸 (Arg) 循环相关的氨基酸、精氨琥珀酸、Arg、鸟氨酸和 Cit，以及γ-氨基丁酸、甘氨酸、组氨酸和烟酰胺腺嘌呤l -Cit 处理的肝脏中含有丰富的二核苷酸。相比之下，含有脂肪酸、氨基酸和环磷酸腺苷的 24 种化合物在 l 中含量较低-Cit 集团。这些数据表明，在1 -Cit 处理的肉鸡中出现活跃的 Cit-Arg 循环、TCA 循环代谢和低活性的脂肪酸代谢。