RESUMO
AIMS: The protective effects of Bacillus amyloliquefaciens(CCT7935), Bacillus subtilis(CCT7935), Bacillus licheniformis (CCT 7836), and Bacillus coagulans (CCT 0199) against lipopolysaccharide (LPS)-induced intestinal inflammation were investigated. METHODS AND RESULTS: Male Swiss mice were assigned into six groups: control group, LPS group, LPS + B. subtilis (CCT7935) group, LPS + B. licheniformis (CCT 7836) group, LPS + B. amyloliquefaciens (CCT7935) group, and LPS + B. coagulans (CCT 0199) group. Each mouse of the groups Bacillus received 1 × 109 colony-forming units of Bacillus once daily by oral gavage during 30 days. Twenty-four hours after the last dose of Bacillus, all groups, except the control group, were intraperitoneally injected with LPS in the single dose of 15 mg kg-1. The mice were euthanized 24 h after the LPS administration. Histological alterations, myeloperoxidase activity, and nitrite levels were analyzed in the gut of mice and the inflammatory cytokines were analyzed in the gut and in the blood. The results demonstrate that the mice challenged with LPS presented the villi shortened and damaged, which were significantly protected by B. coagulans and B. amyloliquefaciens. Furthermore, all Bacillus tested were effective in preventing against the increase of myeloperoxidase activity, while B. amyloliquefaciens and B. subtilis prevented the increase of nitrite and IL-1ß levels in the gut of mice induced with LPS was decreased only B. subtilis. LPS also elevated the IL-1 ß, IL-6, and IL-10 levels in the blood, and these alterations were significantly suppressed by Bacillus, especially by B. subtilis. CONCLUSIONS: The study suggests that the Bacillus investigated in this study might be effective therapeutic agents for preventing intestinal inflammation, because they decrease the inflammatory process an protect against tissue damage.