Effects of Gram-negative probiotic E. coli strain Nissle 1917 (EcN) on the production of nitric oxide (NO) and cytokines were determined in cultures of resident peritoneal cells of rats. The cells (2 x 10(6)/mL) were cultured for 24 h in the presence of live EcN suspension (EcN-Susp), bacteria-free supernatant of this suspension (Sup-EcN), and LPS of EcN origin (LPS-EcN). The biosynthesis of NO was substantially enhanced using live bacteria counts as low as 10(3)/mL applied in the form of EcN-Susp. The same NO-enhancing effect was produced by the correspondingly diluted Sup-EcN. It was found that Sup-EcN contained relatively high amounts of LPS. Administration of the LPS-EcN mimicked the high NO-augmenting activities of both Sup-EcN and EcN-Susp. However, the activity of LPS-EcN was significantly less pronounced than were the activities of Sup-EcN and EcN-Susp containing identical amounts of LPS. The NO-stimulatory effects of the EcN preparations were completely inhibited by polymyxin B. All LPS-EcN and correspondingly diluted Sup-EcN and EcN-Susp stimulated the secretion of cytokines TNF-alpha, IL-1beta, IL-6, IL-10 and VEGF. Also these effects were abrogated by polymyxin B. In contrast to the effects on NO production, the cytokine-stimulatory effects were significantly less pronounced after the exposure of the cells to Sup-EcN and EcN-Susp than to the identical amounts of LPS-EcN. It may be concluded that the in vitro stimulatory effects of EcN on NO and cytokine production are mediated by LPS. It is suggested that the immunostimulatory activity of LPS is modulated by EcN-derived factor(s), the nature of which remains to be identified.

• MeSH
• Bacterial Infections immunology   microbiology   MeSH
• Cytokines immunology   MeSH
• Escherichia coli immunology   metabolism   MeSH
• Rats MeSH
• Cells, Cultured MeSH
• Humans MeSH
• Lipopolysaccharides immunology   metabolism   MeSH
• Disease Models, Animal MeSH
• Nitric Oxide immunology   MeSH
• Peritoneal Cavity cytology   microbiology   MeSH
• Rats, Wistar MeSH
• Probiotics * MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Cytokines MeSH
• Lipopolysaccharides MeSH
• Nitric Oxide MeSH

Our study examined whether repeated preventive oral administration of live probiotic bacterial strains Escherichia coli O83:K24:H31 (Ec O83), Escherichia coli Nissle 1917 O6:K5:H1 (Ec Nis) and Lactobacillus casei DN 114001 (Lc) can protect mice against dextran sodium sulfate (DSS)-induced colitis. A significant decrease in average symptom score was observed in Ec O83-, Ec Nis- and Lc-pretreated group (p < 0.05). Significant differences in body mass loss between Lc pretreated mice with DSS-induced colitis were found when compared with nontreated mice (p < 0.05). PBS pretreated mice had a significantly shorter colon than Ec O83-, Ec Nis- and Lc-pretreated mice (p < 0.05). Administration of Lc significantly decreased the severity of DSS induced histological marks of inflammation (p < 0.05). A significant difference (p < 0.05) was also found in specific IgA level against given probiotic in enteral fluid between colitic mice and healthy mice pretreated with Ec 083 and Ec Nis.

• MeSH
• Administration, Oral MeSH
• Escherichia coli MeSH
• Histocytochemistry MeSH
• Immunoglobulin A analysis   MeSH
• Colon microbiology   MeSH
• Lacticaseibacillus casei MeSH
• Disease Models, Animal MeSH
• Mice, Inbred BALB C MeSH
• Mice MeSH
• Probiotics pharmacology   MeSH
• Dextran Sulfate adverse effects   MeSH
• Intestinal Mucosa immunology   pathology   MeSH
• Colitis, Ulcerative chemically induced   immunology   prevention & control   MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Immunoglobulin A MeSH
• Dextran Sulfate MeSH

Probiotics modulate production of both cytokine and antimicrobial peptides. This effect can be regarded as a part of complex interplay between them and the host.

• MeSH
• Bifidobacterium immunology   MeSH
• Cytokines metabolism   MeSH
• Antimicrobial Cationic Peptides metabolism   MeSH
• Lactobacillus immunology   MeSH
• Humans MeSH
• Probiotics pharmacology   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Cytokines MeSH
• Antimicrobial Cationic Peptides MeSH