The effects of S-nitrosoglutathione on intestinal ischemia reperfusion injury and acute lung injury in rats: Roles of oxidative stress and NF-kB

Background: Intestinal ischemia and reperfusion (I/R) induces oxidative stress, inflammatory response, and acute lung injury. S-nitrosoglutathione (GSNO), a nitric oxide donor, has been documented to have protective effects on experimental ischemia models. Aim: The aim of this study was to examine the effect of GSNO on I/R-induced intestine and lung damage and detect the potential mechanisms emphasizing the protective role of GSNO. Methods: Intestinal I/R was induced by occluding the superior mesenteric artery for 30 min followed by reperfusion for 180 min. GSNO was administered intravenously before reperfusion period (0.25 mg/kg). The levels of lipid peroxidation, reduced glutathione, and myeloperoxidase (MPO), histopathological evaluation and immunohistochemical expressions of both nuclear factor KappaB (NF-?B) and inducible nitric oxide (iNOS) in intestine and lung tissues were assessed. Results: Histolopathologic evaluation demonstrated that intestinal I/R induced severe damages in the intestine and the lung tissues. Histopathological scores decreased with GSNO treatment. GSNO treatment reduced lipid peroxidation and MPO levels and inhibited expression of NF-?B and iNOS in the intestine. Conclusion: Our results suggest that GSNO treatment may ameliorate the intestinal and lung injury in rats, at least in part, by inhibiting inflammatory response and oxidative stress. © 2018 Elsevier Lt

Erythropoietin stimulates wound healing and angiogenesis in mice

Erythropoietin exerts hematopoietic effects by stimulating proliferation of early erythroid precursors. Nonhematopoietic effects of erythropoietin have also been shown. It may act as a new angiogenic factor in wound healing. This study aimed to investigate the effect of systemic administration of recombinant human erythropoietin on wound healing in mice. Dorsal incisional wounds were performed in mice, which were then divided into two groups; a group treated for 7 days with recombinant human erythropoietin, and a control group. Sacrificing animals on day 7, the wound tissues were collected for analysis of wound breaking strength, malondialdehyde, a marker of lipid peroxidation, hydroxyproline, an index of reparative collagen deposition, reduced glutathione levels, and for histological evaluation. The immunohistochemical determination of vascular endothelial growth factor (VEGF) which is believed to be the most prevalent angiogenic factor throughout the skin repair process, was also studied. The treatment significantly increased wound breaking strength by decreasing malondialdehyde and increasing hydroxyproline levels on day 7 after wounding. No statistically meaningful change was observed in reduced glutathione content. VEGF was immunostained significantly more on wound tissue of treated animals compared to the control group. Recombinant human erythropoietin treatment may be effective in wound healing due to inhibition of lipid peroxidation, deposition of collagen, and VEGF expression in wound area. Copyright © Taylor & Francis Group, LLC

Pharmacological preconditioning with erythropoietin reduces ischemia-reperfusion injury in the small intestine of rats

Aims: Considering the implications that arose from several recent experimental studies using recombinant human erythropoietin in rodents, erythropoietin has been regarded as a pharmacological preconditioning agent. The purpose of the present study was to evaluate whether erythropoietin has a preconditioning effect against ischemia and reperfusion injury in the small intestine of the rat. Main methods: Intestinal ischemia was induced in male Wistar rats by clamping the superior mesenteric artery for 30 min, followed by reperfusion for 180 min. Recombinant human erythropoietin (1000 or 3000 U/kg) or vehicle was administered intraperitoneally 24 h prior to ischemia. After collection of ileal tissue, evaluation of damage was based on measurements of the accumulation of polymorphonuclear neutrophils by technetium-99m-labeled leukocyte uptake, content of malondialdehyde, reduced glutathione, contractile responses to agonists, and an evaluation of histopathological features in intestinal tissue. Key findings: Treatment with erythropoietin 24 h before ischemia significantly reduced the tissue content of malondialdehyde and increased that of reduced glutathione. Pretreatment also significantly suppressed leukocyte infiltration into the postischemic tissue, as evidenced by the lower content of myeloperoxidase and technetium-99m-labeled leukocytes. Physiological and histopathological improvements were also significant with the rHuEpo treatment. Significance: Results of the present study indicate that rHuEpo is an effective preconditioning agent in ischemic injury of the small intestine. Protection provided by recombinant human erythropoietin is closely related to the inhibition of oxidative stress and leukocyte infiltration, which might be among the possible protective mechanisms of erythropoietin in intestinal ischemia and reperfusion. © 2009 Elsevier Inc. All rights reserved