0148-6071105/2901-0036$03.00/0 J OURNAL OF PARENTERAL AND E NTERAL N UTRITION Vol. 29, No. 1 Printed in U S. A. Copyright© 2005 by the American Society for Pa renteral and Enteral Nutrition Original Communications The Effect of Preventive Use of Alanyl-Glutamine on Diaphragm Muscle Function in Cecal Ligation and Puncture-Induced Sepsis Model Nurcan Doruk, MD*; Belgin Buyukakilli, PhDt ; Sebnem Atici, MD, PhD*; Ismail Cinel, MD, PhD*; Leyla Cinel, MD*; Lulufer Tamer, PhD§; Dincer Avian, MDII; Egemen Bilgin, MD*; and Ugur Oral, MD * From the * Departments of Anesthesiology and Reanimation, ! Biophysics, t Pathology, §Bioch e mistry, and ! !Pediatric Surgery, Mersin University School of Medicine , Me rsin, Turkey ABSTRACT. Background: Low muscle glutamine levels during sepsis are associated with reduced protein synthesis and ele- vated protein breakdown, in particular myofibrillar protein breakdown. Thus, in a cecal ligation and puncture (CLP}-in- duced sepsis model in the rat, we hypothesized that glutamine pretreatment would protect the diaphragm muscle function. Methods: Eighty-four male Wistar rats weighing between 180 g and 200 g received standard amino acid solution 1.2 g kg- 1 per day intraperitoneally (IP) or standard amino acid solution 1.2 g kg- 1 per day plus alanyl-glutamine (GLN) 0.25 g kg - 1 per day (IP) during the first 6 days of the experiment. On the seventh day, CLP or sham procedures were applied. The sham and CLP groups were equally divided into 3 subgroups according to the termination of the experiment, which took place at either the 24th hour, 48th hour, or 72nd hour. After the compound muscle action potentials (CMAP) were recorded from the diaphragms of the rats at these selected times, they were decapitated under ketamine/xylazine anesthesia, and diaphragms were harvested for biochemical and histopathological examination. Results: The Sepsis is the leading cause of mortality in intensive care units. Respiratory muscle dysfunction, especially diaphragmatic dysfunction, plays an important role in respiratory failure, which was demonstrated as a major cause of high mortality rates in sepsis. 1 • 2 Specif- ically, recent evidence has shown the reduction of .respiratory muscle contractility as a mechanism of dia- phragmatic dysfunction during sepsis. Although the role of reactive oxygen/nitrogen species and Ca + 2 - ATPase was previously mentioned in the mechanism, the pathophysiology of respiratory muscle contractility is not fully understood. The occurrence of the functional organ insufficien- cies in sepsis depends on the prolonged duration of sepsis3-which is characterized by wasting of lean body mass. 5 The muscle wasting results primarily from accelerated breakdown of the long-living myofibrillar proteins, and the preventive role of nutrition was dem- Received for publication Nove mber 8, 2003. Accepted for publication October 11, 2004. Correspondence: Nurcan Doruk, MD, Menderes Mh Baka nlik Cd Liparis Sitesi, F Blok 6/13 33280 Mezitli, Mersin , Turkey. Electronic mail may be sent to nurcan66@hotmail.com. 36 mean area and amplitude of CMAP were significantly larger in sham+GLN groups when compared with CLP and CLP+GLN groups at all times (p < . 05). Diaphragm Ca + 2 -ATPase levels were found to be significantly decreased in CLP group at all times compared to sham groups (p < .05). Diaphragm reduced glutathione levels were significantly higher in sham+GLN groups when compared with CLP and CLP+GLN groups at all times (p < .05). In histopathologic assessment, moderate neu- trophil infiltration, which was observed in CLP48, was signifi- cantly reduced with .alanyl-glutamine supplementation in CLP+GLN48 group (p < .05). Conclusions: This study showed that glutamine pretreatment did not improve diaphragm mus- cle function, but prevented the biochemical and histopatholog- ical changes in diaphragmatic muscle in CLP-induced sepsi s. However, further studies are needed to clarify whether a higher dose of glutamine supplementation might protect the diaphra g- matic muscle functions. (jounzal of Parenteral and Ente ral Nutri- tion 29:36-43, 2005) onstrated. 6 • 7 Glutamine, an abundant amino acid, is "conditionally" essential for nutrition in sepsis. Research into the metabolic role of glutamine in sepsis suggests that a conditional deficiency occurs because of increased and altered tissue demands, which exceed endogenous production. 3 Low muscle glutamine levels during sepsis are associated with this reduced protein synthesis and elevated protein breakdown, in particu- lar myofibrillar protein breakdown. 7 - 9 Besides the piv- otal role in muscle pathophysiology, it has been dem- onstrated that glutamine can significantly attenu ate proinflammatory cytokine release, protect against end- organ damage, and decrease mortality rates in sep- sis. 1o,n We hypothesized that GLN pretreatment given to the rat in vivo would protect the diaphragmatic muscle function in cecal ligation and puncture (CLP)-induced sepsis model. To measure the glutamine pretreatment effect in this model, diaphragmatic muscle function was determined by compound muscle action potential (CMAP) electrophysiologically and by diaphr agm Ca+ 2 -ATPase and reduced glutathione (GSH) levels biochemically. In addition, histopathological findings