Wang Lei, Hou Yongqing, Yi Dan, Li Yongtang, Ding Binying, Zhu Huiling, Liu Jian, Xiao Hang, Wu Guoyao
Hubei Key Laboratory of Animal Nutrition and Feed Science, Hubei Collaborative Innovation Center for Animal Nutrition and Feed Safety, Wuhan Polytechnic University, Wuhan, 430023, China.
Amino Acids. 2015 Jul;47(7):1309-18. doi: 10.1007/s00726-015-1966-5. Epub 2015 Mar 21.
There is growing interest in glutamate as a functional amino acid in nutrition and health. This study was conducted to determine whether glutamate precursor α-ketoglutarate (AKG) could alleviate lipopolysaccharide (LPS)-induced liver injury in young pigs. Twenty-four piglets were randomly assigned to the control, LPS, or LPS + AKG group. Piglets in the control and LPS groups were fed a basal diet, whereas piglets in the NAC group were fed the basal diet supplemented with 1 % AKG. On days 10, 12, 14, and 16 of the trial, piglets in the LPS and LPS + AKG groups received intraperitoneal administration of LPS (80 μg/kg BW), whereas piglets in the control group received the same volume of saline. On day 16 of the trial, blood samples were collected 3 h after LPS or saline injection. Twenty-four hours post-administration of LPS or saline (on day 17 of the trial), piglets were killed to obtain liver for analysis. Dietary AKG supplementation alleviated LPS-induced histomorphological abnormalities and mitigated LPS-induced increases in aspartate aminotransferase (AST) activity and AST/ALT ratio (P < 0.05). Compared with the LPS group, dietary supplementation with AKG decreased plasma glutamate concentration, while increasing hepatic concentrations of glutamate, glutamine, leucine, asparagine, lysine, alanine, serine, threonine, valine, and phenylalanine (P < 0.05). LPS challenge dramatically increased concentrations of malondialdehyde and decreased glutathione peroxidase activity in the liver. Additionally, LPS challenge enhanced concentrations of AMP and total protein, as well as RNA/DNA and total protein/DNA ratios, while decreasing hepatic ADP concentrations. These adverse effects of LPS challenge were ameliorated by AKG supplementation. Collectively, dietary AKG supplementation provides a new means to ameliorate LPS-induced liver injury by increasing anti-oxidative capacity and improving energy metabolism in young pigs.
谷氨酸作为营养与健康领域的一种功能性氨基酸，正日益受到关注。本研究旨在确定谷氨酸前体α-酮戊二酸（AKG）是否能减轻脂多糖（LPS）诱导的幼猪肝损伤。24头仔猪被随机分为对照组、LPS组或LPS + AKG组。对照组和LPS组的仔猪饲喂基础日粮，而LPS + AKG组的仔猪饲喂添加1% AKG的基础日粮。在试验的第10、12、14和16天，LPS组和LPS + AKG组的仔猪腹腔注射LPS（80 μg/kg体重），而对照组的仔猪注射相同体积的生理盐水。在试验的第16天，于注射LPS或生理盐水3小时后采集血样。在注射LPS或生理盐水24小时后（试验的第17天），处死仔猪以获取肝脏进行分析。日粮中添加AKG减轻了LPS诱导的组织形态学异常，并减轻了LPS诱导的天冬氨酸转氨酶（AST）活性和AST/ALT比值的升高（P < 0.05）。与LPS组相比，日粮中添加AKG降低了血浆谷氨酸浓度，同时增加了肝脏中谷氨酸、谷氨酰胺、亮氨酸、天冬酰胺、赖氨酸、丙氨酸、丝氨酸、苏氨酸、缬氨酸和苯丙氨酸的浓度（P < 0.05）。LPS刺激显著增加了肝脏中丙二醛的浓度并降低了谷胱甘肽过氧化物酶的活性。此外，LPS刺激提高了AMP和总蛋白的浓度，以及RNA/DNA和总蛋白/DNA比值，同时降低了肝脏中ADP的浓度。LPS刺激的这些不良影响通过添加AKG得到了改善。总体而言，日粮中添加AKG通过提高抗氧化能力和改善幼猪的能量代谢，为减轻LPS诱导的肝损伤提供了一种新方法。
