This experiment was conducted to evaluate whether pretreatment with fenofibrate could mitigate acute lung injury (ALI) in a mice model of intestinal ischemia/reperfusion (I/R). Male C57BL/6 mice were randomly assigned into three groups (n = 6): sham, intestinal I/R + vehicle, and intestinal I/R + fenofibrate. Intestinal I/R was achieved by clamping the superior mesenteric artery. Fenofibrate (100 mg/kg) or equal volume of vehicle was injected intraperitoneally 60 minutes before the ischemia. At the end of experiment, measurement of pathohistological score, inflammatory mediators and other markers were performed. In addition, a 24-hour survival experiment was conducted in intestinal I/R mice treated with fenofibrate or vehicle. The chief results were as anticipated. Pathohistological evaluation indicated that fenofibrate ameliorated the local intestine damage and distant lung injury. Pretreatment with fenofibrate significantly decreased inflammatory factors in both the intestine and the lung. Consistently, renal creatine levels and hepatic ALT levels were significantly decreased in the fenofibrate group. Moreover, serum systemic inflammatory response indicators were significantly alleviated in the fenofibrate group. In addition, fenofibrate administration significantly improved the survival rate. Collectively, our data indicated that pretreatment with fenofibrate prior to ischemia attenuated intestinal I/R injury and ALI. Acute lung injury (ALI) is a critically severe, life-threatening condition in ICU, characterized by high mortality of approximately 40% 1 . ALI, along with its more severe form, acute respiratory distress syndrome, often results from a massive insult to the lung, whether be the direct alveolar infiltration or the indirect effects of systemic inflammatory response syndrome or multiple organ dysfunction syndromes 2 . An effective treatment of this life-threatening disorder calls for a better understanding of the molecular pathophysiology of ALI. The intestine is recognized to be one of the largest immune barrier systems and to be the source of bacteria and endotoxins in the body 3 . Previous reports indicate that the intestinal organ plays a crucial role in the development of ALI 4 . Mesenteric artery ischemia, a commonly seen critical state during small bowel transplantation or trauma, may lead to intestinal ischemia/reperfusion (I/R) injury. During the process of intestinal I/R injury, local bacteria overgrow and translocate, gastrointestinal mobility decreases, and mucosal permeability increases, all of which subsequently lead to the local intestine damage or distant lung injuries through the activation of systemic inflammatory response syndrome or multiple organ dysfunction syndromes 5,6 . Intestinal I/R is, therefore, a useful model for the investigation of pathophysiological mechanism of indirect ALI. Fenofibrate is known as an agonist of the peroxisome proliferator-activated receptor -α (PPARα ), the nuclear receptor superfamily member 7 . As a nuclear receptor activator, fenofibrate up-regulates or down-regulates genes that are involved in many pathophysiological processes, such as oxidative stress, inflammation, and leukocyte endothelium interactions 8, 9 . Recent studies have demonstrated an anti-oxidant, anti-inflammatory, and anti-ischemic role of fenofibrate to attenuate I/R injury in kidney 10,11 , liver 12 , brain 13,14 and heart 15 . But to date there are no literatures reporting the protective effects of fenofibrate in I/R injury in the organ of intestine. Moreover, the functional significance of fenofibrate in the intestinal I/R-induced ALI remains unclear. Therefore, this experiment is aimed to investigate whether fenofibrate administration would ameliorate the lung injury and inflammation in the model of intestinal I/R injury. Animals. The male C57BL/6 mice (8-10-wk-old; 20 ± 2 g) were purchased from Charles River (Beijing, China). Mice were kept in a temperature (21 ± 2 °C) and humidity (60 ± 5%) controlled room on a 12-hour light/dark cycle. They were fed a standard mice chow and water ad liblitum. All experiments were performed in accordance with the Declaration of Helsinki and were approved by the Institutional Animal Ethical Committee of the Peking Union Medical College Hospital.
Output: Protective effects of fenofibrate against acute lung injury induced by intestinal ischemia/reperfusion in mice OPEN