title: Melatonin reduces bacterial translocation after intestinal ischemia-reperfusion injury.
abstract: Melatonin, the primary pineal hormone, has been reported to protect from oxidative injury after ischemia-reperfusion (IR). The aim of this study was to evaluate the effects of exogenous melatonin on intestinal integrity, ileal colonization, and bacterial translocation 45-minute after mesenteric IR. Sixteen male ACI rats randomly divided into two groups underwent 45-minutes intestinal ischemia by clamping the superior mesenteric artery. One hour prior to ischemia, study animals (n=8, group A) were treated with melatonin (10 mg/kg IP) while control animals (n=8, group B) received the same volume of saline solution. An additional six animals underwent laparotomy and served as a sham-operated group. Animals were sacrificed 24 hours after reperfusion; peritoneal swabs and biopsies of liver, spleen, lung, mesenteric lymph nodes, cecum, and terminal ileum were obtained for microbiology. The ileum samples were also processed for histopathological evaluation of IR-induced injury. Twenty-four hours after reperfusion bacterial translocation to the peritoneal cavity present in all group B animals was reduced to 37.5% among those that were melatonin-treated (group A; P <.05). Furthermore bacterial translocation to mesenteric lymph nodes, spleen, and liver was significantly lower in group A than group B (P <.05). Although cecal and ileal counts did not differ between the two groups, ileal counts from control animals showed increased colonization. Accordingly, a single injection of exogenous melatonin significantly reduced the intestinal IR injury and prevented bacterial translocation.
authors.affiliation: University of Rome "Tor Vergata." Rome, Italy. piersileri@yahoo.com
authors.forename: P
authors.initials: P
authors.lastname: Sileri
authors.forename: G S
authors.initials: GS
authors.lastname: Sica
authors.forename: P
authors.initials: P
authors.lastname: Gentileschi
authors.forename: M
authors.initials: M
authors.lastname: Venza
authors.forename: D
authors.initials: D
authors.lastname: Benavoli
authors.forename: T
authors.initials: T
authors.lastname: Jarzembowski
authors.forename: A
authors.initials: A
authors.lastname: Manzelli
authors.forename: A L
authors.initials: AL
authors.lastname: Gaspari
mesh_terms: D000818:Animals; D018988:Bacterial Translocation / Q000187:drug effects*; D004195:Disease Models, Animal; D007422:Intestines / Q000098:blood supply*; D008099:Liver / Q000382:microbiology; D008168:Lung / Q000382:microbiology; D008198:Lymph Nodes / Q000382:microbiology; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D010537:Peritoneum / Q000382:microbiology; D051381:Rats; D011912:Rats, Inbred ACI; D015427:Reperfusion Injury / Q000517:prevention & control*; D013154:Spleen / Q000382:microbiology
chemical_list: D008550:Melatonin