RESUMO
Abstract Purpose: To analyze the effects of ischemic preconditioning (IPC) in the expression of apoptosis-related genes in rat small intestine subjected to ischemia and reperfusion. Methods: Thirty anesthetized rats underwent laparotomy and were drive into five groups: control (CG); ischemia (IG); ischemia and reperfusion (IRG); IPC and ischemia (IG+IPC); IPC and ischemia and reperfusion (I/RG+IPC). Intestinal ischemia was performed by clamping the superior mesenteric artery for 60 minutes, whereas reperfusion lasted for 120 minutes. IPC was carried out by one cycle of 5 minutes of ischemia followed by 10 minutes of reperfusion prior to the prolonged 60-minutes-ischemia and 120-minutes-reperfusion. Thereafter, the rats were euthanized and samples of small intestine were processed for histology and gene expression. Results: Histology of myenteric plexus showed a higher presence of neurons presenting pyknotic nuclei and condensed chromatin in the IG and IRG. IG+IPC and I/RG+IPC groups exhibited neurons with preserved volume and nuclei, along with significant up-regulation of the anti-apoptotic protein Bcl2l1 and down-regulation of pro-apoptotic genes. Moreover, Bax/Bcl2 ratio was lower in the groups subjected to IPC, indicating a protective effect of IPC against apoptosis. Conclusion: Ischemic preconditioning protect rat small intestine against ischemia/reperfusion injury, reducing morphologic lesions and apoptosis.
Assuntos
Animais , Masculino , Traumatismo por Reperfusão/prevenção & controle , Apoptose/genética , Precondicionamento Isquêmico/métodos , Proteínas Reguladoras de Apoptose/análise , Jejuno/irrigação sanguínea , Jejuno/patologia , Valores de Referência , Distribuição Aleatória , Regulação para Baixo , Expressão Gênica , Reprodutibilidade dos Testes , Ratos Wistar , Artéria Mesentérica Superior , Constrição , Células Endoteliais/patologia , Proteínas Reguladoras de Apoptose/genética , Reação em Cadeia da Polimerase em Tempo Real , Isquemia Mesentérica/genética , Isquemia Mesentérica/patologiaRESUMO
Abstract Purpose: To investigate the gene expression related to inflammation on mice subjected to intestinal ischemia and reperfusion (I/R) and treated with ischemic preconditioning (IPC). Methods: Thirty rats (EPM-Wistar), distributed in five groups of six animals each, were underwent anesthesia and laparotomy. The ischemia time was standardized in 60 minutes and the reperfusion time 120 minutes. IPC was standardized in 5 minutes of ischemia followed by 10 minutes of reperfusion accomplished before I/R. The control group was submitted only to anesthesia and laparotomy. The other groups were submitted to ischemia, I/R, ischemia + IPC and I/R + IPC. It was collected a small intestine sample to analyses by Quantitative Polymerase Chain Reaction in real Time (RT-qPCR) and histological analyses. It was studied 27 genes. Results: The groups that received IPC presented downregulation of genes, observed in of genes in IPC+ischemia group and IPC+I/R group. Data analysis by clusters showed upregulation in I/R group, however in IPC groups occurred downregulation of genes related to inflammation. Conclusion: The ischemia/reperfusion promoted upregulation of genes related to inflammation, while ischemic preconditioning promoted downregulation of these genes.