Lafutidine inhibits Helicobacter pylori-induced interleukin-8 production in human gastric epithelial cells

Reduced lesions in chickens with Clostridium perfringens-induced necrotic enteritis by Lactobacillus fermentum 1.20291

Previous studies have demonstrated that Lactobacillus has anti-inflammatory properties, but the protective functions of Lactobacillus and mechanisms of inhibition of necrotic enteritis (NE) in the intestines of chickens have not been fully clarified. In the present study, we selected a probiotic strain, Lactobacillus fermentum 1.2029, which has good adhesive ability and a high survival rate in low pH and bile salts. The objective of this study was to examine the anti-inflammatory properties of L. fermentum 1.2029 against NE in chickens. Two hundred forty 1-d-old male Arbor Acres broilers were blocked into 3 experimental groups as follows: (I) nonchallenge control group, (II) Clostridium perfringens challenge group, and (III) C. perfringens challenge + L. fermentum 1.2029 group. Lactobacillus fermentum 1.2029 (1.0 mL/d, 10(8) cfu/mL) was orally administered daily to group III during the course of the experiment, and all uninfected control chickens were inoculated accordingly with the same volume of PBS. Clostridium perfringens (0.5 mL on d 1 and 1.0 mL on d 14 to 21, 10(8) cfu/mL) was administered to chickens in group II. At 28 d, scoring of gross NE lesions was performed. Ileal segments of approximately 2 cm from 24 chickens in each experimental group were collected and fixed in 4% (wt/vol) neutral-buffered formalin solution for histological scoring. Ileal mucosa samples were also collected for mRNA analysis by real-time PCR. The results showed that L. fermentum 1.2029 reduced the severity of NE lesions in chickens. Histological scores revealed that L. fermentum 1.2029 also reduced the inflammation damage of NE in chickens. Changes in cytokines and Toll-like receptors (TLR) were determined, and L. fermentum 1.2029 was found to increase interleukin-10 levels and reduce interferon-γ and TLR2 levels in NE-infected chickens. The results showed that L. fermentum 1.2029 was able to regulate the intestinal mucosal immune response and ameliorate inflammation by changing expression levels of cytokines and TLR.

Lactobacilli inhibit interleukin-8 production induced by Helicobacter pylori lipopolysaccharide-activated Toll-like receptor 4

AIM: To investigate the effect of Lactobacillus bulgaricus (LBG) on the Toll-like receptor 4 (TLR4) pathway and interleukin-8 (IL-8) production in SGC-7901 cells treated with Helicobacter pyloriSydney strain 1 lipopolysaccharide (H pyloriSS1-LPS).

METHODS: SGC-7901 cells were treated with H pyloriSS1-LPS in the presence or absence of pretreatment for 1 h with viable LBG or supernatant recovered from LBG culture MRS broth (LBG-_S). Cellular lysates were prepared for Western blot with anti-TLR4, anti-transforming growth factor β-activated kinase 1 (TAK1), anti-phospho-TAK1, anti-nuclear factor κB (NF-κB), anti-p38 mitogen-activated protein kinase (p38MAPK), and anti-phospho-p38MAPK antibodies. The amount of IL-8 in cell culture medium was measured by ELISA.

RESULTS: H pyloriSS1-LPS up-regulated the expression of TLR4, stimulated the phosphorylation of TAK1, subsequently enhanced the activation of NF-κB and the phosphorylation of p38MAPK in a time-dependent manner, leading to augmentation of IL-8 production in SGC-7901 cells. Viable LBG or LBG-_S pretreatment attenuated the expression of TLR4, inhibited the phosphorylation of TAK1 and p38MAPK, prevented the activation of NF-κB, and consequently blocked IL-8 production.

CONCLUSION: H pyloriSS1-LPS induces IL-8 production through activating TLR4 signaling in SGC-7901 cells and viable LBG or LBG-_S prevents H pyloriSS1-LPS-mediated IL-8 production via inhibition of the TLR4 pathway.

Mucosal proinflammatory cytokine and chemokine expression of gastroduodenal lesions in Crohn's disease

BACKGROUND

The stomach and the duodenum are frequent sites of involvement by diminutive lesions in Crohn's disease (CD).

AIM

To assess mucosal proinflammatory cytokines and chemokines in gastroduodenal lesions of CD.

METHODS

13C-Urea breath test and upper endoscopy were performed in 29 CD patients and seven control subjects, and biopsy specimens were obtained from the gastric cardia and the duodenum. Histology and mucosal levels of IL-1beta, IL-8/CXCL8 and RANTES/CCL5 were assessed and compared according to the presence of gastric cardial lesion [bamboo joint-like appearance (BJA)] and duodenal lesion (notched appearance, aphthous erosion and polypoid lesion). In 11 CD patients, these procedures were repeatedly performed after administration of famotidine.

RESULTS

H. pylori was less frequently positive in CD patients than in controls (10% vs. 71%, P = 0.003). Prevalence of cardial and duodenal lesion was significantly higher in CD than in controls (59% vs. 0%, P = 0.008 for gastric lesion; 45% vs. 0%, P = 0.034 for duodenal lesion). There were no differences in IL-1beta, IL-8 and RANTES between CD and controls. Duodenal mucosal IL-1beta and IL-8 were significantly higher in positive duodenal lesion than in negative duodenal lesion. However, there were no such differences with respect to cardial lesions. Endoscopic findings remained unchanged after administration of famotidine, while there was a trend towards decreases in IL-1beta and IL-8 in the gastric cardia.

CONCLUSIONS

The pathogenesis of diminutive lesions of CD may be different between the stomach and the duodenum. Famotidine may not have a therapeutic effect on duodenal lesion in CD.