title: [Effect of L-alanyl-L-glutamine on expression of insulin-like growth factor-1 in intestinal tissues of low-birth-weight newborn rats with hypoxia/reoxygenation-induced intestinal injury].
abstract: OBJECTIVE
  To study the effect of L-alanyl-L-glutamine (Ala-Gln) on the levels of insulin-like growth factor-1 (IGF-1) and IGF-1 receptor (IGF-1R) in the intestinal tissues of low-birth-weight (LBW) newborn rats with hypoxia/reoxygenation-induced intestinal injury.
  
  
  METHODS
  Pregnant rats were fed with or without smoking. The rats born by those fed without smoking were included in group A; for the rats born by those fed with smoking, normal-birth-weight rats were included in group B, and LBW rats were randomly divided into control group (group C), hypoxia/reoxygenation (H/R) group (group D), and Ala-Gln group (group E). Each group consisted of 24 newborn rats. The rats in groups D and E received H/R treatment twice a day for three consecutive days to establish an intestinal injury model; the rats in group E were intraperitoneally injected with Ala-Gln (10 ml/kg) before daily H/R treatment, while those in groups C and D were given an equal dose of normal saline by intraperitoneal injections. On days 4, 7, and 10 after birth, 8 rats were sacrificed in each group to collect intestinal tissues. The IGF-1 levels in intestinal tissues were measured using ELISA, and IGF-1R levels were measured by immunohistochemistry.
  
  
  RESULTS
  There were no significant differences in IGF-1 and IGF-1R levels between groups A and B at all time points. The levels of IGF-1 and IGF-1R in group C kept increasing, were higher than those in other groups on day 7 (P<0.05), and reached a normal level on day 10, without significant differences compared with those in groups A and B. Group D had significantly lower IGF-1 and IGF-1R levels than group C at all time points (P<0.05). The levels of IGF-1 and IGF-1R in group E were lower than those in group C on days 4 and 7 (P<0.05), but they increased to approximately the levels in group C and were significantly higher than those in group D on day 10.
  
  
  CONCLUSIONS
  Intrauterine and postnatal hypoxia may induce intestinal injury in LBW newborn rats, and parenteral administration of high-dose Ala-Gln can reduce hypoxia-induced intestinal injury. Therefore, Ala-Gln has a protective effect against hypoxia-induced intestinal injury.
authors.affiliation: Department of Neonatology, Shenzhen Bao'an District Maternal and Child Health Care Hospital, Shenzhen, Guangdong 518133, China. sunetemal@163.com.
authors.forename: Fen
authors.initials: F
authors.lastname: Xu
authors.forename: Chuan-Rui
authors.initials: CR
authors.lastname: Zhu
authors.forename: Yuan-Li
authors.initials: YL
authors.lastname: Zhan
authors.forename: Guang-Jin
authors.initials: GJ
authors.lastname: Lu
authors.forename: Hao-Bin
authors.initials: HB
authors.lastname: Su
mesh_terms: D000818:Animals; D001724:Birth Weight; D004151:Dipeptides / Q000494:pharmacology*; D005260:Female; D000860:Hypoxia / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D007422:Intestines / Q000737:chemistry*; D008297:Male; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017526:Receptor, IGF Type 1 / Q000032:analysis
chemical_list: D004151:Dipeptides; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1; C054122:alanylglutamine