RESUMEN
OBJECTIVES: Necrotizing enterocolitis is a severe multifactorial intestinal disorder that primarily affects preterm newborns, causing 20-40% mortality and morbidity. Intestinal fatty acid-binding protein has been reported to be a biomarker for the detection of intestinal injuries. Our aim was to assess intestinal tissue injury and the molecular expression of intestinal fatty acid-binding protein over time in a necrotizing enterocolitis model. METHODS: A total of 144 Newborn rats were divided into two groups: 1) Control, which received breastfeeding (n=72) and 2) Necrotizing Enterocolitis, which received formula feeding and underwent hypoxia and hypothermia (n=72). A total of six time points of ischemia (2 times a day for 3 days; 12 pups for each time point) were examined. Samples were collected for analysis of body weight, morphological and histological characteristics, intestinal weight, intestinal weight/body weight ratio, injury grade, and intestinal fatty acid-binding protein levels. RESULTS: Body and intestinal weights were lower in the Necrotizing Enterocolitis group than in the Control group (p<0.005 and p<0.0005, respectively). The intestinal weight/body weight ratio was higher in the Necrotizing Enterocolitis group than in the Control group (p<0.005) only at the sixth ischemia time point. The Necrotizing Enterocolitis group displayed higher expression of intestinal fatty acid-binding protein (p<0.0005) and showed greater tissue damage than the Control group. CONCLUSION: Intestinal fatty acid-binding protein was an efficient marker of ischemic injury to the intestine and a good correlation was demonstrated between the time of ischemic injury and the grade of intestinal injury.
Asunto(s)
Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/patología , Proteínas de Unión a Ácidos Grasos/metabolismo , Íleon/patología , Animales , Animales Recién Nacidos , Biomarcadores/análisis , Western Blotting , Peso Corporal , Modelos Animales de Enfermedad , Proteínas de Unión a Ácidos Grasos/análisis , Hipoxia/patología , Íleon/irrigación sanguínea , Inmunohistoquímica , Isquemia/patología , Distribución Aleatoria , Ratas Sprague-Dawley , Valores de Referencia , Índice de Severidad de la Enfermedad , Factores de TiempoRESUMEN
BACKGROUND: Congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia and pulmonary hypertension. Tracheal occlusion (TO) stimulates fetal lung growth and maturation and reverse vascular changes responsible for pulmonary hypertension, which are related to mechanisms involving nitric oxide (NO) in CDH. We aim to evaluate the effect of TO and ventilation on NO pathways. METHODS: Eight groups were created: (1) control; (2) control ventilated (CV); (3) CDH (CDH); (4) CDH ventilated (CDHV); (5) TO control; (6) TO ventilated; (7) TO + CDH; and (8) TO + CDH ventilated (CDHTOV). Fetuses were weighed, and volume ventilated for 30 min after harvested. Total lung weight and the ratio of total lung weight to body weight, thickness of the middle layer of the pulmonary arteriole, and the air space diameter were measured. The NO synthase inducible and NO synthase inducible were performed by immunohistochemistry and Western blotting. RESULTS: The total lung weight and the ratio of total lung weight to body weight decreased in animals with nitrofen and also after ventilation for all groups (P < 0.05). The thickness of the middle layer of the pulmonary arteriole decreased in all groups with TO when compared with controls (P < 0.001). The air space diameter decreased after ventilation in the CDHTOV compared to the TO + nitrofen-induced CDH (P < 0.001). Compared to nonventilated cohorts, NO synthase inducible increased in CV and TO ventilated (P < 0.001) and decreased in CDHV and CDHTOV (P < 0.001). NO synthase inducible increased in CV and CDHV (P < 0.001) and decreased in the TO control and CDHTOV (P < 0.001). CONCLUSIONS: TO and ventilation alter the NO pathway with possible implications in reducing the pulmonary hypertension in CDH.
Asunto(s)
Terapias Fetales , Hernias Diafragmáticas Congénitas/terapia , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico/metabolismo , Respiración Artificial , Oclusión Terapéutica , Animales , Biomarcadores/metabolismo , Western Blotting , Femenino , Terapias Fetales/métodos , Hernias Diafragmáticas Congénitas/metabolismo , Hernias Diafragmáticas Congénitas/fisiopatología , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/prevención & control , Inmunohistoquímica , Pulmón/embriología , Pulmón/metabolismo , Óxido Nítrico Sintasa/metabolismo , Tamaño de los Órganos , Ratas , Ratas Sprague-DawleyRESUMEN
OBJECTIVES: Necrotizing enterocolitis is a severe multifactorial intestinal disorder that primarily affects preterm newborns, causing 20-40% mortality and morbidity. Intestinal fatty acid-binding protein has been reported to be a biomarker for the detection of intestinal injuries. Our aim was to assess intestinal tissue injury and the molecular expression of intestinal fatty acid-binding protein over time in a necrotizing enterocolitis model. METHODS: A total of 144 Newborn rats were divided into two groups: 1) Control, which received breastfeeding (n=72) and 2) Necrotizing Enterocolitis, which received formula feeding and underwent hypoxia and hypothermia (n=72). A total of six time points of ischemia (2 times a day for 3 days; 12 pups for each time point) were examined. Samples were collected for analysis of body weight, morphological and histological characteristics, intestinal weight, intestinal weight/body weight ratio, injury grade, and intestinal fatty acid-binding protein levels. RESULTS: Body and intestinal weights were lower in the Necrotizing Enterocolitis group than in the Control group (p<0.005 and p<0.0005, respectively). The intestinal weight/body weight ratio was higher in the Necrotizing Enterocolitis group than in the Control group (p<0.005) only at the sixth ischemia time point. The Necrotizing Enterocolitis group displayed higher expression of intestinal fatty acid-binding protein (p<0.0005) and showed greater tissue damage than the Control group. CONCLUSION: Intestinal fatty acid-binding protein was an efficient marker of ischemic injury to the intestine and a good correlation was demonstrated between the time of ischemic injury and the grade of intestinal injury.
Asunto(s)
Animales , Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/patología , Proteínas de Unión a Ácidos Grasos/metabolismo , Íleon/patología , Valores de Referencia , Factores de Tiempo , Índice de Severidad de la Enfermedad , Peso Corporal , Inmunohistoquímica , Biomarcadores/análisis , Distribución Aleatoria , Western Blotting , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Proteínas de Unión a Ácidos Grasos/análisis , Íleon/irrigación sanguínea , Isquemia/patología , Animales Recién Nacidos , Hipoxia/patologíaRESUMEN
PURPOSE: The use of dexamethasone (Dx) stimulates growth, fetal lung maturation and can improve pulmonary hypertension in congenital diaphragmatic hernia (CDH). Our aim was to evaluate the effect of Dx on the lung after fetal pulmonary ventilation in the CDH rat model. METHODS: Some groups underwent prenatal treatment with dexamethasone (0.4 mg/kg) that was given at 18.5 gestational day (GD). Sprague-Dawley rat fetuses were divided into groups: control (C); ventilated control (CV); control exposed to dexamethasone (CDx); ventilated control exposed to dexamethasone (CVDx); congenital diaphragmatic hernia (CDH), ventilated CDH (CDHV), CDH exposed to dexamethasone (CDHDx) and ventilated CDH exposed to dexamethasone (CDHVDx). At 21.5 GD fetuses were delivered by C-section, weighed and ventilated for 30 min. We analyzed the lung morphometry by Masson's Trichrome stain, and VEGF, VEGFR1, VEGFR2 and NOS3 expression by immunohistochemistry. RESULTS: All fetuses with CDH, with or without prenatal dexamethasone showed lung and body weight lower than control fetuses (p < 0.05). All groups that received dexamethasone showed a decrease in the medial muscular layer of arterioles, the internal diameter of the air spaces (Lma) and length of parenchymal transection/airspace ratio (p < 0.05). In the immunohistochemistry, VEGF decreased more in CDHDV group (p < 0.05). VEGFR1 showed no difference, whereas VEGFR2 decreased significantly in the CDHDV group (p < 0.05). NOS3 increased in the group CDHDV (p < 0.05). CONCLUSION: The use of prenatal dexamethasone added to ventilation alters the VEGF and NO pathways.