Abstract Purpose: To evaluate the effect of hyperbaric oxygenation (HBO) on the expression of the genes antioxidant glutathione peroxidase 4 (Gpx4) and lactoperoxidase (Lpo) in the lung of mice subjected to intestinal ischemia and reperfusion (IIR). Methods: Control group (CG) in which were subjected to anesthesia, laparotomy and observation for 120 minutes; an ischemia and reperfusion group (IRG) subjected to anesthesia, laparotomy, small bowel ischemia for 60 minutes and reperfusion for 60 minutes; and three groups treated with HBO during ischemia (HBOG + I), during reperfusion (HBOG + R) and during ischemia and reperfusion (HBOG + IR). Studied 84 genes of oxidative stress by the method (RT-qPCR). Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student’s t-test p<0.05). Results: Gpx4 and Lpo were hiperexpressed on IRG, showing a correlation with these genes with lung oxidative stress. Treated with HBO, there was a significant reduction on genic expression on HBOG+I. Conclusion: Hyperbaric oxygenation showed to be associated with decreased expression of these antioxidant genes, suggesting a beneficial effect on the mechanism of pulmonary oxidative stress whenever applied during the ischemia.

Abstract Purpose: To investigate the effects of hyperbaric oxygenation (HBO) on intestinal ischemia and reperfusion (IR) injury, we evaluated the expression of 84 genes related to oxidative stress and the antioxidant response in mouse hearts. Methods: Four groups were subjected to 60 minutes of intestinal ischemia followed by 60 minutes of reperfusion: IRG, ischemia and reperfusion group without HBO; HBO-IG, which received HBO during ischemia; HBO-RG, which received HBO during reperfusion; and HBO-IRG, which received HBO during ischemia and reperfusion. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes. The (RT-qPCR) method was applied. Genes with expression levels three times below or above the threshold cycle were considered significantly hypoexpressed or hyperexpressed, respectively (Student’s t-test p<0.05). Results: Eight genes (9.52%) were hyperexpressed in the IRG. When the HBO groups were compared to the IRG, we found a decrease in the expression of eight genes in the HBO-IG, five genes in the HBO-RG, and seven genes in the HBO-IRG. Conclusion: The reduction in the expression of genes related to oxidative stress and antioxidant defense following HBO in mouse hearts resulting from intestinal IR injury was more favorable during the ischemic period than during the reperfusion period.

FUNDAMENTO: O fenômeno da isquemia e reperfusão intestinal é um evento frequente na clínica e está associado a repercussões deletérias em órgãos a distância, em especial ao coração. OBJETIVO: Investigar a expressão gênica do estresse oxidativo e defesa antioxidante no coração de camundongos isogênicos, submetidos a isquemia e reperfusão intestinal (IR). MÉTODOS: Doze camundongos (C57BL/6) foram distribuídos em dois grupos: Grupo IR (GIR) com 60 min de oclusão da artéria mesentérica superior, seguidos de 60 min de reperfusão. Grupo Controle (GC) submetidos a anestesia e a laparotomia sem o procedimento de IR observados por 120 min. As amostras de intestino e coração foram processadas pelo método (RT-qPCR / Reverse transcriptase - quantitative Polymerase Chain Reaction) para determinar a expressão gênica de 84 genes relacionados ao estresse oxidativo ("t" de Student, p < 0,05). RESULTADOS: Observou-se no tecido intestinal (GIR) uma expressão significantemente aumentada em 65 (74,71%) genes em relação ao tecido normal (GC), e 37 (44,04%) genes estiveram hiperexpressos (maior que três vezes o limiar permitido pelo algoritmo). No tocante aos efeitos da I/R intestinal a distância no tecido cardíaco verificou-se a expressão significantemente aumentada de 28 genes (33,33%), mas somente oito genes (9,52%) se hiperexpressaram três vezes acima do limiar. Quatro (7,14%) desses oito genes se expressaram simultaneamente nos tecidos intestinal e cardíaco. No GIR notaram-se cardiomiócitos com núcleos de menor tamanho, picnóticos, ricos em heterocromatina e raros nucléolos, indicando sofrimento cardíaco. CONCLUSÃO: A I/R intestinal promoveu a hiperexpressão estatisticamente significante de oito genes associados ao estresse oxidativo a distância no tecido miocárdico.

BACKGROUND: Intestinal ischemia-reperfusion is a frequent clinical event associated to injury in distant organs, especially the heart. OBJECTIVE: To investigate the gene expression of oxidative stress and antioxidant defense in the heart of inbred mice subjected to intestinal ischemia and reperfusion (IR). METHODS: Twelve mice (C57BL / 6) were assigned to: IR Group (GIR) with 60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion; Control Group (CG) which underwent anesthesia and laparotomy without IR procedure and was observed for 120 minutes. Intestine and heart samples were processed using the RT-qPCR / Reverse transcriptase-quantitative Polymerase Chain Reaction method for the gene expression of 84 genes related to oxidative stress and oxidative defense (Student's "t" test, p < 0.05). RESULTS: The intestinal tissue (GIR) was noted to have an up-regulation of 65 genes (74.71%) in comparison to normal tissue (CG), and 37 genes (44.04%) were hyper-expressed (greater than three times the threshold allowed by the algorithm). Regarding the remote effects of intestinal I/R in cardiac tissue an up-regulation of 28 genes (33.33%) was seen, but only eight genes (9.52%) were hyper-expressed three times above threshold. Four (7.14%) of these eight genes were expressed in both intestinal and cardiac tissues. Cardiomyocytes with smaller and pyknotic nuclei, rich in heterochromatin with rare nucleoli, indicating cardiac distress, were observed in the GIR. CONCLUSION: Intestinal I/R caused a statistically significant over expression of 8 genes associated with oxidative stress in remote myocardial tissue.

PURPOSE: To determine the gene expression profile associated with oxidative stress and antioxidant defense in the lung tissue of mice subjected to intestinal ischemia and reperfusion.METHODS: Twelve male, inbred mice (C57BL/6) were randomly assigned to one of two groups. The control group (CG) underwent anesthesia and laparotomy and was observed for 120 minutes; the ischemia/reperfusion group (IRG) was subjected to anesthesia, laparotomy, and ischemia of the small intestine for 60 minutes and to 60 minutes of reperfusion. A pool of six mice from each group was subjected to a reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to analyze the oxidative stress and antioxidant defense genes. All genes that were up-regulated or down-regulated greater than three-fold, based on the algorithm [2^(ΔΔCt)], were considered to be biologically meaningful.RESULTS: Out of a total of 84 genes in the lung that are related to oxidative stress, 67 (79.7%) were up-regulated and 17 (20.2%) were down-regulated. Only two genes (2.3%), Lpo (lactoperoxidase) (+3.51) and Gpx4 (glutathione peroxidase) (+4.10), were expressed above the three-fold threshold, while none of the down-regulated genes were expressed outside of this threshold.CONCLUSION: The intestinal ischemia/reperfusion injury promoted a gene expression profile consisting of the positive expression of oxidative genes in a remote organ. This suggests that activate signaling pathways are implicated in both cell survival and the maintenance of genome integrity in the lung.

PURPOSE: To determine the gene expressions profile related to the oxidative stress and the antioxidant response in the kidneys of mice subjected to intestinal ischemia and reperfusion. METHODS: Twelve inbred mice (C57BL/6) were randomly assigned to one of two groups: the control group (CG) underwent anesthesia and was observed for 120 min and the ischemia/reperfusion group (IRG), animals were anesthetized and subjected to laparotomy and ischemia for 60 minutes followed by 60 minutes of reperfusion. The expressions of 84 genes from the kidney were determined by the Reverse Transcription qualitative Polymerase Chain Reaction (RT-qPCR). All genes that were up regulated by more than threefold using the algorithm [2(ΔΔCt)] were considered statically significant (p<0.05). RESULTS: In the IRG group 29 (34.52%) of 84 genes, were up regulated by more than threefold. The genes that were differentially up regulated in the glutathione peroxidase cluster (10 genes): were Gpx2 and Gpx7. The genes that were up regulated in the peroxidase cluster (16 genes) were following: Duox1, Epx, Lpo, Mpo, Ptgs2, Rag2, Serpinb1b, Tmod1 and Tpo. The genes that up regulated in the reactive oxygen species cluster (16 genes): Il19, Il22, Nos2, Nox1, Noxa1, Noxo1, Recql4 and Sod2. The genes that were up regulated in the oxidative stress cluster (22 genes) were: Mpp4, Nudt15, Upc3 and Xpa. The genes that were up regulated in the oxygen carriers cluster (12 genes) were: Hbq1, Mb, Ngb, Slc38a1 and Xirp1. The peroxiredoxins genes (10) showed no consistent differential regulation. CONCLUSION: The genes related to oxidative stress and antioxidant defense showed increased expression in renal tissue trigged intestinal ischemia and reperfusion.

OBJETIVO: Determinar o perfil de expressão dos genes associados com estresse oxidativo e contribuir para estabelecer parâmetros sobre o papel das familias de enzimas relacionadas com a lesão de isquemia / reperfusão intestinal. MÉTODOS: Doze camundongos machos isogênicos (C57BL/6) foram distribuídos aleatoriamente: Grupo Controle (CG) submetido à laparotomia anestesia, e observado por 120min; Grupo isquemia/reperfusão (IRG) submetido à anestesia, laparotomia, 60min de isquemia do intestino delgado e 60min de reperfusão. Um pool dos seis camundongos de cada grupo foi submetido ao protocolo de qPCR-RT (seis famílias) para o estresse oxidativo e defesa antioxidante. RESULTADOS: Dos 84 genes investigados, 64 (76,2%) tiveram expressão estatística significante e 20 (23,8%) não apresentaram diferença estatística com o grupo controle. Dos 64 genes expressos de forma significante, 60 (93,7%) foram hiper-expressos e 04 (6,3%) foram hipo-expressos. Do grupo sem expressão estatisticamente significante, 12 genes foram hiper e 8 genes foram hipo-expressos. Surpreendentemente, 37 (44,04%) apresentaram expressão três maior que o limiar de normalidade e arbitrariamente os valores foram considerados como altamente significantes. Assim, 37 genes (44,04%) foram hiper-expressos de modo muito significante. Nos demais, 47 (55,9%) dos genes foram hiper-expressos menos de três vezes (35 genes - 41,6%) ou hipo-expressos menos de três vezes(12 genes - 14,3%). CONCLUSÃO: A isquemia e reperfusão intestinal promoveu um perfil de hiper-expressão global das seis familias de genes relacionados com estresse oxidativo antioxidante e defesa antioxidante.

PURPOSE: To determine the profile of gene expressions associated with oxidative stress and thereby contribute to establish parameters about the role of enzyme clusters related to the ischemia/reperfusion intestinal injury. METHODS: Twelve male inbred mice (C57BL/6) were randomly assigned: Control Group (CG) submitted to anesthesia, laparotomy and observed by 120min; Ischemia/reperfusion Group (IRG) submitted to anesthesia, laparotomy, 60min of small bowel ischemia and 60min of reperfusion. A pool of six samples was submitted to the qPCR-RT protocol (six clusters) for mouse oxidative stress and antioxidant defense pathways. RESULTS: On the 84 genes investigated, 64 (76.2%) had statistic significant expression and 20 (23.8%) showed no statistical difference to the control group. From these 64 significantly expressed genes, 60 (93.7%) were up-regulated and 04 (6.3%) were down-regulated. From the group with no statistical significantly expression, 12 genes were up-regulated and 8 genes were down-regulated. Surprisingly, 37 (44.04%) showed a higher than threefold up-regulation and then arbitrarily the values was considered as a very significant. Thus, 37 genes (44.04%) were expressed very significantly up-regulated. The remained 47 (55.9%) genes were up-regulated less than three folds (35 genes - 41.6%) or down-regulated less than three folds (12 genes - 14.3%). CONCLUSION: The intestinal ischemia and reperfusion promote a global hyper-expression profile of six different clusters genes related to antioxidant defense and oxidative stress.