Ischemic preconditioning modifies mortality and inflammatory response

Abstract

PURPOSE:To evaluate the effect of ischemic preconditioning on mortality, inflammatory mediators and oxidative stress after intestinal ischemia and reperfusion. METHODS:Male Wistar rats were allocated according to the period of ischemia with or without ischemic preconditioning which consist on clamping the superior mesenteric artery for 10 minutes followed by reperfusion for 10 minutes before the sustained ischemia period. Mortality was assessed in Phase 1 study, and the CINC-1, CINC-2 and MDA levels in the lungs were analyzed in Phase 2. RESULTS:Mortality was lower in the ischemic preconditioning group subjected to 90 minutes of ischemia compared to the group without ischemic preconditioning (I-90: 50% and IPC-90: 15%, p=0.018), and it was lower in the ischemic preconditioning group as a whole compared to the groups without ischemic preconditioning (IPC-14% and I=30%, p=0.006). Lower levels of MDA, CINC-1, and CINC-2 were observed in the animals that were subjected to ischemic preconditioning compared to the animals that were not (MDA: I-45=1.23 nmol/mg protein, and IPC-45=0.62 nmol/mg protein, p=0.0333; CINC-1: I-45=0.82 ng/mL and IPC-45=0.67 ng/mL, p=0.041; CINC-2: I-45=0.52 ng/mL and IPC-45=0.35 ng/mL, p=0.032). CONCLUSION:Ischemic preconditioning reduces mortality, inflammatory process and oxidative stress in rats subjected to intestinal ischemia and reperfusion.

The role of ischemic preconditioning in gene expression related to inflammation in a rat model of intestinal ischemia-reperfusion injury

“…The model with 5 minutes of ischemia and 10 minutes of reperfusion was chosen for this study because it has been demonstrated to protect organs against I/R injury, and also due to our aim to study precocious changes 9 . When the intestinal ischemia was fulfilled for 90 minutes, a lack of response occurred in the animal, which was unable to produce and release the inflammatory mediators; therefore, the animals that underwent IPC before 90 minutes of ischemia also had a theoretically greater capacity to provide a response to injury 9 . For this reason, we choose 60 minutes of ischemia, for allow to assess the tissue answer to IPC stimulus.…”

“…This process usually occurs in clinical situations, such as mesenteric ischemia, septic shock, extensive burns and intestinal transplantation. Thus, I/R plays an important role in the pathogenesis of systemic inflammatory response syndrome (SIRS) and Multiple Organ Dysfunction Syndrome (MODS), since it is associated with an increase in intestinal permeability, which is one of the causal factors of bacterial translocation that allows intestinal bacterium to burn to extra-intestinal sites 9,10 .…”

“…One of these is ischemic preconditioning (IPC). IPC is an adaptive response of tissue to brief periods of ischemia, which provides prior conditioning and serves to protect tissue from prolonged subsequent ischemic damage and reperfusion injury 7,9 . Ischemic tolerance is induced by the regulation of endothelial function, blood flow, reduced macrophage and neutrophil activity 7,11 .…”

Preconditioning in neuroprotection: From hypoxia to ischemia

“…In a very recent study, IPC reduced mortality in rats subjected to intestinal ischemia. Additionally, IPC results in a reduction of the inflammatory process and oxidative stress (Pinheiro et al, 2016). From these studies, we can understand that IPC has been demonstrated in multiple organ systems and shown to be effective.…”

“…Zhao et al also concluded that HPC decreased infarct size by inhibiting free radical generation (Zhao et al, 2006). A recent study found that IPC reduces oxidative stress (Pinheiro et al, 2016). Enzymes like catalase, superoxide dismutase (SOD), lactoperoxidase, and glutathione peroxidase have been investigated to determine their roles in HPC (Duan et al, 1999; Garnier et al, 2001; Koca et al, 2010; Li et al, 2008; Stroev et al, 2005).…”