Effects of Gut Microflora on Hepatic Damage After Acute Liver Injury in Rats

Background: Liver injury often causes disruption of the gut microflora. The aim of this work was to evaluate the effects of microflora variations oil acute liver injury. Methods: Sprague-Dawley rats received saline, probiotics, Escherichia coli,Salmonella enteritidis. or gentamicin via daily gavage for 7 days. Acute liver injury was induced on the eighth day by intraperitoneal injection of D-galactosamine except for the normal group. Samples were collected 24 hours later. Bacterial translocation (BT) was evaluated front the liver, spleen, kidney, and mesenteric lymph nodes. Liver enzymes, histologic analysis, endotoxin, serum tumor necrosis factor-alpha, interleukin (IL)-6, IL-10, IL-12 CD3(+) and CD4(+) T cells in peripheral blood and Peyer's patches, intestinal bacteria, and intestinal mucosal ultrastructure were Studied. Results: Orally administered probiotics, nanpathogenic E. coli, and gentamicin, respectively, markedly attenuated liver damage, decreased BT, and decreased the levels of serum tumor necrosis factor-alpha, IL-6, IL-10, and IL-12. Treatment with S. enteritidis had opposite results. Only orally supplemented S. enteritidis significantly affected the CD3(+) and CD4(+) T cells counts in peripheral blood and Peyer's patches. Conclusions: We demonstrated that modifications in gut microflora had different effects on the prevention or exacerbation of acute liver injury. Moreover, alterations in gut microflora affected liver damage through three major factors: BT and the release of local gut cytokine and endotoxin.