title: Enteral supplementation of alanyl-glutamine attenuates the up-regulation of beta-defensin-2 protein in lung injury induced by intestinal ischemia reperfusion in rats.
abstract: BACKGROUND
  Beta-defensin-2 (BD-2), an endogenous antimicrobial peptide, plays a key role in immune response against microbial invasion. This study aimed to observe the effect of Alanyl-Glutamine (Ala-Gln) on BD-2 protein expression in pulmonary tissues after intestinal ischemia reperfusion (IIR) in rats and to investigate its correlations to pulmonary inflammatory and oxidative injury.
  
  
  METHODS
  Rats in IIR and the two treatment groups were subjected to intestine ischemia for 60 min and those in the treatment groups were administered orally with Ala-Gln or alanine (Ala) respectively. Lung tissues were harvested to detect the BD-2 protein expression. Concentrations of Tumor necrosis factor (TNF)-α and malondialdehyde (MDA) as well as superoxide dismutase (SOD) activity in lung tissues were determined simultaneously.
  
  
  RESULTS
  Ala-Gln attenuated the up-regulation of BD-2 expression (p < 0.05) and TNF-α (p < 0.05), MDA (p < 0.05) levels, as well as the reduction of SOD activity (p < 0.05) in lung tissues after IIR. But Ala did not exert significant effects. BD-2 protein in lung tissues was positively correlated to local TNF-α level (p < 0.01) and MDA concentration (p < 0.01) with statistical significance.
  
  
  CONCLUSIONS
  Ala-Gln can relieve the IIR-induced up-regulation of BD-2 protein expression in the lung of rats, which involves anti-inflammation and anti-oxidation mechanisms.
authors.affiliation: Department of Oncological Surgery, Yinzhou People's Hospital, Ningbo, China; Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Xiao-Bin
authors.initials: XB
authors.lastname: Wu
authors.affiliation: Department of Oncological Surgery, Yinzhou People's Hospital, Ningbo, China.
authors.forename: Jia-Gen
authors.initials: JG
authors.lastname: Li
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Yi-Jia
authors.initials: YJ
authors.lastname: Lin
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Hong-Lei
authors.initials: HL
authors.lastname: Chen
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Hu
authors.initials: H
authors.lastname: Song
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Zhong-Hui
authors.initials: ZH
authors.lastname: Liu
authors.affiliation: Department of Gastrointestinal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. Electronic address: pengjunsheng@tom.com.
authors.forename: Jun-Sheng
authors.initials: JS
authors.lastname: Peng
mesh_terms: D055371:Acute Lung Injury / Q000209:etiology / Q000378:metabolism* / Q000628:therapy*; D000818:Animals; D004151:Dipeptides / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004750:Enteral Nutrition; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000150:complications* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D015854:Up-Regulation; D023083:beta-Defensins / Q000378:metabolism*
chemical_list: D004151:Dipeptides; D014409:Tumor Necrosis Factor-alpha; D023083:beta-Defensins; C054122:alanylglutamine
keywords: Beta-defensin-2; Glutamine; Intestines; Lung injury; Reperfusion injury