Ringer's ethyl pyruvate solution ameliorates ischemia/reperfusion-induced intestinal mucosal injury in rats

Harvard University, Cambridge, Massachusetts, United States
Critical Care Medicine (Impact Factor: 6.31). 09/2001; 29(8):1513-8. DOI: 10.1097/00003246-200108000-00003
Source: PubMed


Pyruvate has been shown to be protective in numerous in vitro and in vivo models of oxidant-mediated cellular or organ system injury. Unfortunately, the usefulness of pyruvate as a therapeutic agent is abrogated by its very poor stability in solution. In an effort to take advantage of the ability of pyruvate to scavenge reactive oxygen species while avoiding the problems associated with the instability of pyruvate in solution, we sought to determine whether a simple derivative, ethyl pyruvate, would be protective in an animal model of reactive oxygen species-mediated tissue injury, namely mesenteric ischemia and reperfusion in rats.
Prospective, randomized trial.
Animal research center.
Male Sprague-Dawley rats.
Under general anesthesia, rats were subjected to 60 mins of mesenteric ischemia followed by 60 mins of reperfusion. Controls (n = 6) received intravenous lactated Ringer's solution according this dosing schedule: 1.5 mL/kg bolus before ischemia, 3.0 mL/kg bolus before resuscitation, and 1.5 by continuous infusion. Two experimental groups received similar volumes of either pyruvate (n = 6 each) or ethyl pyruvate (n = 9) solution made up exactly like lactated Ringer's solution except for the substitution of either pyruvate or ethyl pyruvate for lactate, respectively.
To obtain tissues for assessing mucosal permeability and histology, five 10-cm long segments of small intestine were obtained at the following time points: baseline, after 30 and 60 mins of ischemia, and after 30 and 60 mins of reperfusion. Mucosal permeability to fluorescein isothiocyanate dextran (molecular weight 4000 Da) was assessed ex vivo by using an everted gut sac method. Compared with controls, treatment of rats with either pyruvate solution or ethyl pyruvate solution significantly ameliorated the development of intestinal mucosal hyperpermeability during the reperfusion. Treatment with ethyl pyruvate solution also significantly decreased the extent of histologic mucosal damage after mesenteric reperfusion.
Treatment with Ringer's ethyl pyruvate solution ameliorated structural and functional damage to the intestinal mucosa in a rat model of mesenteric ischemia/reperfusion. Ethyl pyruvate solution warrants further evaluation as a novel therapeutic agent for preventing oxidant-mediated injury in various disease states.

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    • "Inflammation was characterized by airway neutrophilia and eosinophilia, along with elevated BAL cytokines, raised levels of IL-4 and IFN-γ in supernatant of cultured lymphocytes, and increased total serum IgE, accompanied by airway epithelial goblet cell hyperplasia. EP has been shown to be an effective anti-inflammatory agent in a wide variety of in vivo and in vitro models of inflammation-mediated cellular or tissue injury, including severe sepsis, hemorrhagic shock, ischemia/reperfusion-induced intestinal mucosal injury and ileus induced by bowel manipulation in mice [21] [22] [23] [24] [25] [26]. However, EP used for treatment in TDI-induced asthma has not been studied yet. "
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    • "Ethyl pyruvate (EP) is a stable and lipophilic ester derived from the endogenous metabolite pyruvic acid [13]. The pharmacological effects of EP include downregulation of the secretion of proinflammatory cytokines, amelioration of redox-mediated damage to cells and tissues, and inhibition of apoptosis [14]. "
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    Full-text · Article · Jun 2011 · Mediators of Inflammation
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    • "Following these seminal experiments, ethyl pyruvate has been tested extensively in multiple disease models and species. It improved survival as well as organ function in preclinical models of severe sepsis and endotoxaemia, acute respiratory distress syndrome, haemorrhagic shock and stroke when it was administered within 12–24 h of disease induction in rodents (Sims et al. 2001; Tawadrous et al. 2002; Ulloa et al. 2002; Venkataraman et al. 2002; Yang et al. 2002; Kim et al. 2005; Su et al. 2007; van Zoelen et al. 2007; Karabeyogˇlu et al. 2008; Cai et al. 2009a,b; Cruz et al. 2009) and haemorrhagic shock in swine (Dong et al. 2009). Ethyl pyruvate failed to improve haemodyanic indices in patients during cardiopulmonary bypass in a phase II clinical trial (Bennett-Guerrero et al. 2009). "
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