Efeito da suplementação dietética com L-glutamina na sepse abdominal induzida em rato

Abstract

After the triggering stimulus of trauma or infection, the release of cytokines into the bloodstream plays an important effector and modulator role on the systemic immune response. These cytokines may be pro-inflammatory, stimulating the release of several cell types and other cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), IL-2, IL-6, IL-8, IL-12 and interferon-gamma (IFN-γ); or cytokines with anti-inflammatory effects that inhibit the inflammatory process, in part by reducing the production of several cytokines that positively regulate the response, minimizing the resulting organic damages, such as IL-4 , IL-10, IL-13. L-Glutamine is the most abundant amino acid in the body, with an important role in protein metabolism, acting as a vehicle for nitrogen transport. Its trophic action on the small intestinal mucosa is well known, which makes it an essential component in the maintenance of the bowel structure and function. This study aimed at evaluating the effect of the dietary supplementation with L-glutamine in modulating the inflammatory response in animals submitted to the induction of abdominal sepsis by cecal ligation and puncture (CLP). We used 24 adult male Wistar rats, initially weighing between 200 and 230 g, divided into three groups, each with eight animals as follows: group I (control) sham operation (laparotomy and manipulation of the bowel); group II laparotomy with induction of abdominal sepsis; and group III dietary supplementation with L-glutamine for seven days and after submitted to the induction of abdominal sepsis. Blood samples were collected from all animals before (time 0) and two and four hours (times 1 and 2) after the induction of abdominal sepsis. We verified white blood cell (WBC) count, the plasmatic concentration of pro- and anti-inflammatory cytokines (INF-γ, IL-6 and IL-10), and the microbiological analysis of peritoneal fluid. Blood glucose increased significantly in all groups, comparing them in the beginning and in the end of the experiment (p<0.05). Concerning to IL-10, we observed a significant increase in the animals of group III between times 0 and 2, and times 1 and 2 (p=0.0331 and p=0.0155, respectively). We did not observe any difference in the analysis of the other cytokines (IFN-γ and IL-6) in all groups and at all times. Our findings suggest that dietary supplementation with L-glutamine in animals submitted to the induction of abdominal sepsis with CLP model seems to enhance the anti-inflammatory response, increasing the plasmatic concentration of IL-10, while the concentration of INF-γ and IL-6 did not present significant change.