Article

Glycine reduces tissue lipid peroxidation in hypoxia-reoxygenation-induced necrotizing enterocolitis in rats.

Experimental Surgery, UNIFESP, Brazil.
Acta Cirurgica Brasileira (Impact Factor: 0.57). 01/2006; 21(3):161-7. DOI: 10.1590/S0102-86502006000300008
Source: PubMed

ABSTRACT To assess the protective effect of glycine in an experimental model of Neonatal Necrotizing Enterocolitis (NEC).
Fifty (50) neonatal Wistar rats, from a litter of six female rats and weighing 4 to 6 grams, were used. Five animals were cannibalized and the 45 remaining were distributed into three groups: the G1 normal control group (n=12); the G2 Group (n=16), of animals that underwent hypoxia-reoxygenation (HR); the G3 Group of animals (n=17) that underwent HR following a 5% intraperitoneal glycine infusion. The animals underwent hypoxia in a CO2 chamber receiving an air flow of 100% CO2 for 5 minutes and reoxygenation receiving an O2 flow at 100% for 5 minutes. One centimeter long small bowel and colon segments were prepared for histological analysis. The rest of the bowel was removed in a block and frozen at minus 80 degrees C for homogenization and determination of tissue malondialdehyde (MDA). Tissue lesions were classified as Grade 0 to Grade 5, according to the level of damaged mucosa.
The animals in Group G1 had levels of small bowel and colon lesion significantly smaller as compared to the animals in Groups G2 and G3. The G2 group had mean MDA values significantly higher than the animals in the G1 (p = .015) and G3 (p=0.021) groups. MDA values did not differ significantly (p = 0.992) for the animals in groups G1 and G3.
Glycine reduces tissue MDA levels (a measurement of lipid peroxidation) following HR in neonatal rats.

Download full-text

Full-text

Available from: Karine Furtado Meyer, Sep 17, 2014
1 Follower
 · 
73 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate tissue lesions, especially those of the intestinal innervation, in an excluded jejunal loop subjected to ischemia and reperfusion in rats. To evaluate the role of ischemia and reperfusion lesions in an excluded intestinal loop, four groups of 20 rats were set up: control group (GCEI7) and three experimental groups (GIREI7, GIREI14 and GIREI28). They were all subjected to exclusion of an intestinal segment of six centimeters in length, at a distance of 10 centimeters from the Treitz angle. The 60 animals in the three experimental groups were additionally subjected to ischemia of the vascular pedicle for 30 minutes. The control group and the experimental group GIREI7 were evaluated on the 7th day after the operation. The groups GIREI14 and GIREI28 (which also underwent ischemia) were utilized to evaluate the evolution of the lesion over time, on the 14th and 28th days after the operation, respectively. From the intestinal excluded loop, we take one ring of 0,5 cm distal and proximal, that were fixed in formaline 10% solution in order to do histological (HE) and immuno-hystochemial (PS-100) evaluation (enteric nervous system.) The distal loop was exteriorized in stoma and the proximal part closed with polipropilene 6-0. It was observed a decrease in the number of ganglionic cells in the myenteric plexus in the group subjected to ischemia and reperfusion (GIREI7), in relation to the control group (GCEI7) at the 7th post-operative day (Mann-Whitney test: p = 0.0173 *. Comparing the numbers of ganglionic cells in the myenteric plexus before and after jejunal loop exclusion GCEI7 - (Wilcoxon test: p = 0.0577). GIREI7 - Comparing the numbers of ganglionic cells in the myenteric plexus before and after ischemia (*p = 0.0399). Comparing the percentage variations in ganglionic cells in the myenteric plexus on the 7th, 14th and 28th days after the procedure, in the groups GIREI7, GIREI14 and GIREI28, it was observed that there were no significant alterations. Kruskal-Wallis test: p = 0.6501. There was a decrease in the number of ganglionic cells in the myenteric plexus due to ischemia and reperfusion that did not recover in the late post-operative period.
    Acta Cirurgica Brasileira 03/2007; 22(2):120-4. DOI:10.1590/S0102-86502007000200008 · 0.57 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: PURPOSE: To evaluate the effects of maternal remote ischemic preconditioning (IPCr) in the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation. METHODS: Newborn Wistar rats were divided into three groups. Control Group (CG), Hypoxia and Reoxygenation Group (HRG) and Remote Ischemic Preconditioning Group (IPCrG). Hypoxia and reoxygenation was performed 2x per day, with an interval of 6 hours, on the 1st, 2nd and 3rd days of life, with 10 minutes of CO2 at 100%, followed by 10 minutes O-2 at 100%(HRG/IPCrG). The maternal IPCr was performed 24 hours before delivery by applying a rubber band tourniquet to the left hind limb (IPCrG). Segments of the colon underwent histological (HE) and immunohistochemical analysis for caspase-3 and COX - 2. RESULTS: The histological findings showed no intestinal mucosal damage in the CG group and severe lesions in HRG that was attenuated in the IPCrG (p<0.05). The expression of the apoptotic cells was lower in the HRG group than in the CG and IPCrG. The COX-2 expression was intense in HRG and attenuated in the IPCrG (p<0.05). CONCLUSIONS: Maternal IPCr protected the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation, reducing the morphological alterations and inflammatory response. It ameliorates the occurrence of apoptosis, keeping the physiological process of renewal and regeneration in the epithelial lining of the colonic mucosa.
    Acta cirurgica brasileira / Sociedade Brasileira para Desenvolvimento Pesquisa em Cirurgia 07/2014; 29(7):438-444. DOI:10.1590/S0102-86502014000700005 · 0.48 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Usually an experimental necrotizing enterocolitis experimental model, we Investigated nitric oxide levels in intestinal tissues of newborn mice with or without l-arginine therapy during sessions of ischemia and reoxygenation. Twenty-six newborn mice from the Wistar EPM-1 lineage, weighing from 4.5 to 6.2 g, were randomly assigned to three groups: G-I/R, hypoxia and reoxygenation; G-Arg, l-arginine treatment I/R; and G-CTL, controls. G-I/R and G-Arg mice underwent twice a day during their first 3 days of life exposure to gas chambers with 100% CO(2) for 5 minutes at 22 degrees C before reoxygenation with 100% O(2) for another 5 minutes. After 12 hours, all animals were sedated, laparotomized, and had samples of ileum and colon taken and- either formalin fixed histopathologic examinations or frozen to -80 degrees C for estimation of tissue nitric oxide levels. Intestinal injuries were classified according to the criteria of Chiu et al. The G-I/R and G-Arg groups showed injuries characteristic of necrotizing enterocolitis (NEC) with an improved structural preservation rate in G-Arg. The concentration of nitric oxide in the Ileum was much higher with G-Arg (16.5 +/- 4.9; P = 0.0019) G-I/R (7.3 +/- 2.0). This effect was not observed in the colon: G-I/R = 10.7 +/- 4.6 versus G-Arg = 15.5 +/- 8.7 (P = .2480). Supply of L-arginine increased tissue levels of nitricoxide and reduced morphologic intestinal injury among mice undergoing I/R.
    Transplantation Proceedings 05/2008; 40(3):830-5. DOI:10.1016/j.transproceed.2008.02.044 · 0.95 Impact Factor