title: The effect of aspartate on the energy metabolism in the liver of weanling pigs challenged with lipopolysaccharide.
abstract: OBJECTIVE
  This study was conducted to investigate whether aspartate (Asp) could improve liver energy status in the lipopolysaccharide (LPS)-challenged pigs.
  
  
  METHODS
  Twenty-four weaned pigs were assigned to four treatments: (1) nonchallenged control (control diet and saline-treated); (2) LPS-challenged control (the same control diet and LPS-challenged); (3) LPS + 0.5% Asp treatment (0.5% Asp diet and LPS-challenged); and (4) LPS + 1.0% Asp treatment (a 1.0% Asp diet and LPS-challenged). On d 19, the pigs were injected intraperitoneally with Escherichia coli LPS at 100 μg/kg body weight, and the same volume of 0.9% NaCl solution, respectively. All pigs were slaughtered at 24 h after LPS or saline injection, and the liver was collected for further analysis.
  
  
  RESULTS
  Dietary supplementation with Asp improved liver energy status evidenced by the increased ATP concentration and adenylate energy charges, and the decreased AMP concentration and AMP/ATP ratio (p < 0.05). Asp supplementation increased the mRNA expression of key enzymes in hepatic glycolysis and tricarboxylic acid (TCA) cycle, including pyruvate kinase and citrate synthase (p < 0.05), and had a tendency to increase hepatic pyruvate dehydrogenase and isocitrate dehydrogenase β mRNA expression (p < 0.10). In addition, Asp increased the mRNA expressions of hepatic AMP-activated protein kinase (AMPK) α1, AMPKα2, silent information regulator (Sirt1), and proliferator-activated receptor-γ coactivator 1α (PGC1α) (p < 0.05). Moreover, Asp increased AMPKα phosphorylation (p < 0.05).
  
  
  CONCLUSIONS
  These results indicated that dietary supplementation of Asp could improve energy status in LPS-injured liver, which might result from motivating the metabolism pathway of TCA cycle and glycolysis and stimulating the AMPK signaling pathway.
authors: Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan, 430023, China, ylkp2003@163.com.
authors: Ping
authors: P
authors: Kang
authors: Yulan
authors: Y
authors: Liu
authors: Huiling
authors: H
authors: Zhu
authors: Shuang
authors: S
authors: Li
authors: Haifeng
authors: H
authors: Shi
authors: Feng
authors: F
authors: Chen
authors: Weibo
authors: W
authors: Leng
authors: Dinan
authors: D
authors: Pi
authors: Yongqing
authors: Y
authors: Hou
authors: Dan
authors: D
authors: Yi
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology*; D004032:Diet; D019587:Dietary Supplements; D004734:Energy Metabolism / Q000187:drug effects*; D004926:Escherichia coli / Q000378:metabolism; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000009:adverse effects*; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D056564:Sirtuin 1 / Q000235:genetics / Q000378:metabolism; D013552:Swine; D014886:Weaning
chemical_list: D008070:Lipopolysaccharides; D012333:RNA, Messenger; D001224:Aspartic Acid; D000249:Adenosine Monophosphate; D000255:Adenosine Triphosphate; D055372:AMP-Activated Protein Kinases; D056564:Sirtuin 1